There is nothing wrong with having an active and creative mind.One that thinks outside the box.
That does not mean every innovative idea will pay off.
Seems like Edison said something about discovering 10,000 ways to make a light bulb that did not work.
IMO,if a person only has a 30-06 and a 12 ga,there might be good reason to find versatility by varying loads.
Myself,I have different firearms like different golf clubs.I try to develop the load that maximizes the efficiency of that particular firearm.I am mostly a one load per firearm guy.I learn that combination.( I have 3 different 30-06;s.Each gets a different load! Garand,a 1903A4gery,and a hunting rifle.)But its always the same load.
I use 1 load in my .257 AI,the 115 gr Ballistic Tip and H-4831 SC.
A .357 Max is fairly specialized.I could see having two or loads;A plinker and a 357 max load Maybe one for hunting,one for targets.. But,yes,I'd concentrate on a reliable,repeatable adjustable sight for your needs.Maybe learn that 50 yds is 7 clicks up from bottomed out? or 125 yds is 13 clicks? .Could work.
You might do some serious ballistic calculator work to see if your idea can even be accomplished.
With a handgun,some recoil occurs while the bullet is in the barrel.Fixed sight guns can be somewhat sighted by varying loads.I'm going to leave that variable out of my next comment.
Purely on the flight after the bullet leaves the muzzle,my guess is,there is little drop at 25 yds.Not a lot at 50 yds.Even with a 700 fps load.
I just do not think pouring the coal to the velocity....what? 1800,1900,maybe 2000 fps? will make the difference to put you on target at 200 yds.My guess is that you will still need elevation.
And,for myself,the complexity/logistics of carrying,multiple loads...keeping them organized,not running out of one load...A range card for my sights is simpler.
Then,in my loading room,I'd need more powders....
The K.I.S.S. principle has merit.