Okay, probably a late reply, but here's some of my comments:
First off, about the Pyonta thing, I get the feeling that the only reason why hacks include that is because blue did it. (and type diversity I guess. bug/
fighting makes a bit more sense if you see the Ex form's sprite, but it's still random and extremely "what the hell") The UFO's and the Yukkuris are on the same boat in that regard.
Secondly, while Pyonta is in the "way too deep into fanon" territory, I fail to see how 2hu and the eirin nurse thingy to be any different in that regard. (okay, the latter wasn't actually a puppet, but point still stands.) While there ARE some fanon-esque characters I don't mind, such as Noroiko and satsuki (even 1.8 canon has that in the form of lily black, and satsuki herself is boss-exclusive), it seems a little too "iffy" to me to include fanon puppets. One last minor nitpick on this, but
six Yukkuris? even one is kind of excessive, but six is way too much.
As for the typings themselves, I can see 1.8 typings making more sense, honestly, since as it's been pointed out, 1.5 has a bunch of dark/psychic/normal types and very few of the other types. while 1.8 does suffer from this a bit (IE, still a lot of dark/reason-types, some types like earth and water are pretty rare), it's far more consistent outside of the ice and illusion typings. (and to be fair, what puppets can you see getting those two typings added on anyway, outside of 1.5 sakuya that is.) While there are some derps here and there (case in point: yuugenmagan), it's mostly logical. the only two 1.5 types I'm willing to defend is ice/steel sakuya (not on main sakuya, though, maybe on a tech form or something) and the fire/ice yumemi (way too cool to let go completely, even if I still wouldn't put this on main yumemi. fire/reason is also an interesting typing, however.)
Still, I do wonder how a hybrid of the two would play out, it'd probably end up as only bug, dragon, and rock being added from 1.5, and they'd mostly serve to make certain puppets stand out. (yamame/wriggle, meiling/iku, and suika/tenshi respectively) still, I find that idea at least somewhat interesting, especially since "adding" types is indeed possible in gen III now.
http://www.pokecommunity.com/showthread.php?t=313872As for the megas, I do kinda find last words to be SOMEWHAT more logical, mainly since instead of having a bunch of gems with names like "reimuite" or "ikuite" we could just have one "last word tag" that could act as the last word activation for any puppet that can use it. same mechanics as the mega evolutions, just a more sensible name. (yes, I know most people one here still cringe when they hear the phrase "last word insert-puppet-here" or "LWinsert-puppet-here") However, to be honest, I'm kinda against the whole concept for the same reason why I'm kinda dubious about the 1.5-1.8 type mesh thing above: it just ends up as playing favorites with some of the puppets, as the ones that DON'T get a last word/mega form struggle to stand out. Speaking of that, agastya brought this up in his nitpick corner for AW and it still applies here; some of the last word/mega forms are extremely random, like elly, kogasa, and
the giant catfish.
And finally, abilities, a few nitpicks here: Any idea why female shingyoku gets intimidate, while male shingyoku gets the MUCH less useful for his HA? Kotohime with firm grip is pretty random. (own tempo should just be her only ability), same with kana and prankster. Any idea what "Miracle Star" is on sanae? I can kinda figure out some of the renamed abilities (IE, zombie = mummy), but I can't guess what that one's supposed to be. miracle skin? For things being completely broken, I'm shocked no one's pointed out multiscale lily white yet. (and on that note, multi-skin sounds REALLY odd) Drizzle suwako and drought utsuho just speak for themselves, really. (really, those two abilities would still be broken on things with 200-level BST's) Also, moody koishi and protean patchouli.
overall, as others have pointed out, moving into gen IV itself is a daunting thing when 1.8 kinda carved it's own, non-pokemon niche out for itself. (which the new TPDP is continuing to do, while romhacks themselves seem to be branching out more towards fangames over romhacks as well.) I understand this is just a silly brainstorming thing, though, so it's good to get these thoughts and complaints out every now and then. Still, I need to finish up my own hack, it's been sitting on the bench for way too long, and it's very close to completion.