Provisional there’s a lot of ways to go about balancing that set, but the 3 options I’d consider are taking them all to C9 or just add 3g to the 7, 2g to the 5,6,w to balance the head weights and call it close enough, or glue them as they are and stop thinking. Off the top of my head, I think option 2 gets it close enough you will never notice, but you have this much time invested, don’t let me sway you from doing it the way you want them.

On the ferrules, I have had some that are just too damn tight in the past, I take either sand paper or my hosel cleaning wire brush and run it through the inside of them enough to make a little dust, blow that out and then a q-tip dipped in acetone to melt it back to smooth for sliding purposes, repeat until it’s tight, but you can move it on the tip, grab the hair dryer and get it warm, move into place.

      DC300
      I'm vacillating on tip wt adjustment
      For 5 , 6 irons particularly. There are some who suggest that a progression of swing weights is desirable, making lower lofted irons & longer shafts feel easier to swing , with less wt further from swing axis. My aging related strength distance loss seems very noticeable this year too with driver and 5, 6 irons. I'd just leave off tip wts based on that , but C6 may be too low and cause poor control. I see that with my driver swing as my heavier G15 vs Cleveland UL 270 , much more consistent with heavier club and mostly longer . I like your idea to add small adjustment to 5,6 irons and fgorgetsbout it😃

        Provisional

        You'll find out soon enough! 😉

        Typically, there are 10 cycles between flexes. A typical iron shaft in a woman’s flex would frequency at about 250 cpm; a senior flex, 260 cpm; a man’s regular flex, 270 cpm; a stiff flex, 280 cpm; and an extra stiff flex at 290 cpm.

          "The plans of mice and men gang aft aglay" or per "The Stones , You don't always get what you waaont"

          Perhaps this is why the shafts all feel stout, I wouldn’t worry too much, hit them and judge results.

          Shafts feel more S than Sr. to me after playing 9 anda small bucket at the range.
          But they did go my usual distances and gave straight shots. May be too stout. But...
          I'm going to add some lead tape to bring them all up to swing wt C9 see If that changes feeling they give me after I try them couple of more times. They respond better to a steeper stronger swing. I feel like wt reduction is helping increase club speed too.

            At c9 swing weight, they will feel much stouter. D2 should soften them up closer to A or R flex
            considering their 'stated' cpm. JMO.

              Eguller
              Thanks for the info

              I didn't realize an increase in sw would change feel so much .
              Lots to learn , of which I was aware. Just hoped my shot into the dark would get me close enough . Messing around in the pasture with pw yesterday . As I said, it was straight hitting , with a penetrating trajectory probably lowers dispersion. This will be fine, unless spin is too low to hold the greens . I hit a nice 170 yd 5 iron to green on a parr 4 hole at Shadow Ridge GC , also lower trajectory rolled through and off back side. I have always hit lots of knuckle balls though , from the rough, you know ,my usual location.😂 I may possibly warm to these shafts after a few rounds. My ball striking is not good, so I'm stretching to play these Mizzys anyway. I like the look, and their feel when well struck struck. My scores can't get much worse anyway, so might as well play what I want. I know that the graphite is going to be what makes them friendly enough for Mr Arthritis Geezer. I can always threaten them with my Pings if they misbehave too much.

                Par4QC
                funnyeee!😁
                SWMBO'S line, but she can't resist .
                In trying this exersize , I hoped to to replace the heavy steel DG 300R shafts with much lighter graphite ones better suited for my , ahem, mature years, without sacrificing good dispersion and the soft feeling Mizuno irons promise. I believe that , has been achieved. I was surprised at the lower than expected wts that the Matrix 84 shafted up and their frequency too. I was warned that they play firm, to be fair, but I thought specifying Sr flex would more than accommodate that as I wanted more soft regular than Sr anyway. I'll play around with some lead tape to attempt to dial them in and see if I can get a softer feel . The lower trajectory is a bit of worry too. I almost selected the Grafalloy Prolaunch Axis instead of the Matrix ones for their low kick point, but opted for the heavier , I thought, shaft. Probably what is to be expected by not hiring a good fitter instead of dummies shot into dark.
                It was fun, what t heck.

                    Provisional People do worry too much, sometimes, about the flex. If you are capable of swinging those clubs, & hitting 5i 170, you're doing fine. You swing straight, the ball's going straight. No floppy, twisting shafts.

                        sdandrea1
                        Down hill, hard pan fairway , low, hot knuckle ball out of rough, but it made me happy even after it rolled 3 yds into rough on far side of green. Crappy chip back on green and 2 putts not so much. I was playing members tees to get some extra iron play since shorter sr. tees except parr 5s wouldn't. Driver was driving me off my nut, but I was there to practice with the irons, so what the hey.

                        Classic lofts with the Mizzys so 27* for 5 iron only gives 150 and change for my old man speed unless other factors like wind, fairway rebound, downhill, or a lucky center face strike help out. I do get a charge out of a well struck 5 iron and there are a couple of holes on both muni courses I play where I usually give it a go if I'm feeling frisky. I should be using the 5 wood too, but it's a little too much if I catch it well.

                          Par4QC
                          The Matrix 84 even sr. Flex have a backbone for sure. Viagra must be working for them. Takes a little extra effort to load them seemingly. But If they help my accuracy that will be a happy too. I'll try them out some more before adding lead tape which I expect could smooth feel a bit. If I can find some one around with an available swing wt scale I'll get readings too.

                              This swing wts is interesting parameter. It does have quite an effect in the little I've played with it. Using Value Golf estimator my 7 was C 4.6. Felt very stiff and had to put lots of effort into strikes. I added 4 g. Lead to cavity with noticeable improvement in feel and ability to stike with less effort calculated sw =
                              C6.8. If I change from 63 g Star grip to 40 g Golf Pride sw calcs D 1.2.
                              I have read grip wt justs fools swing wts calcs but it changes total wt and balance. Thinking I'll change the 7 grip and see what effect it has. My Ping iron shafts are counter balanced so I thought that the heavier grips would simulate that a little.
                              Thoughts?

                              Adding weight to the head will soften the shaft flex, which you apparently prefer. Lead tape is cheap
                              and a really good experiment based on what you've experienced so far. A lighter grip will not do that.