I blame the brawl split for causing this stupid oldman/stuck in way/defensive mentaility that a lot of the melee community has. If only PM 3.5 was somehow what brawl was initially.
https://www.youtube.com/watch?v=YJnGRuidOXI#t=36
That's a whole different Universe that wouldn't make sense, and come crashing down because it's not guided by the true Smash destiny time continuum. And you would have killed Melee at EVO and everything sacred (again, the Smash continuum.)
You can't come close to PM even if Sakurai himself wanted to at the time create another Melee based game instead of where he went with Brawl (WHICH, in our current universe, inspired many things PM took anyways).
AND
The last thing you should be worried or concerned about, is Melee players preferring Melee. You should have enough wisdom to know that PM is guided by the Smash time continuum. since Demo v1, and it will grow exponentially as it travels along the path.
And characters changing, even if it is after around a year, is a legitimate excuse. I could quote multiple posts by Hylian and others where they enjoy people finding out "broken" tactics, to remove them. That might be what you want to hear as a designer, but not always for a pioneer who's ready to wholeheartedly put yourself into the game.
And any high level character research like that of Kadano's done for say 2.5 would and will be made useless; and before people could even begin to fully utilize it (which people still haven't for his Melee stuff now). Any intricate strategy that could take a year to come up with, develop, and master, could be cut short by even benign changes to whatever for whatever reason ("I think Squirtle's SH should be lowered again, that'd be cool") or possibly directly for pretentious/over-rated and a hundred other adjective circumstances.