I'm not sure what TakaraTOMY could do to significantly improve on existing MP figures. Cosmetic/aesthetics aside, MP10 isn't really an improvement over MP1 - IMHO MP1 is still the better action figure between the two. MP1 is just jam packed with so many awesome gimmicks and features which MP10 simply lacks. Obviously MP10 was simplified because it also comes with the trailer/combat deck and Roller Car - MP10 is a better all-rounder. MP11 has a better robot mode, but MP3 still has a superior looking jet mode. MP36 looks to have a much better looking robot mode, but MP5 still has a better looking gun mode. So in each of these new incarnations there is some level of trade off rather than an absolute improvement.
I suppose boils down to whether or not you feel that the new figure is a big enough improvement over the previous version to warrant getting it or not. I've preordered MP36 because while the gun mode doesn't look as good as MP5, the improvements in every other aspect of the figure makes it worthwhile. But I know other collectors who disagree and aren't interested in MP36 (it hasn't pre-sold out yet on PC).
But MP5 was always a figure that had room for improvement, so it's not surprising that a new MP Megatron would offer a lot more than the original. MP1 and MP10 are both great figures and it's hard to improve on these figures beyond just aesthetics. The whole new MP Seeker mould might be interesting, as we know that there are issues with Kawamori's MP3 design, some of which MP11 has inherited too. But unless a new rebooted MP is on the disparity level of MP5 v MP36, then I'm likely to just skip it. I might get the mould if it's repainted as a different character - e.g. I never got MP11 Starscream or the redecoes as Skywarp and Thundercracker, but I did get MP Acidstorm and Sunstorm. So if they made a new MP Starscream I'd probably skip it, but I might get it if it were repainted as a blue Rainmaker (I hope that TakaraTOMY names it "Blizzard Storm" (don't really care for the Hasbro name)), Nacelle or Hotlink.