HGSS:
Elite 4 goes down. Not sure how much of the aftergame I'm gonna do. Certainly not doing much for team building enjoyment because some of the changes HGSS made is pretty gag inducing (y halo thar voltorb flip asdas;ljasdkjls). I'll probably just end up catching all the bonus pokes like Suicune/Lati/weather trio etc. Game is pretty much as I remembered GSC except the EXP curve is possibly even lower (although I did end up splitting EXPs for a pretty long time). I don't find the game much better than its predecessor though...probably remains at a 6 or a 6.5.
In terms of Gym leaders, it's a little better around this time. As in, there is a certain bit of balance such that its not a completely cruisathon sans Claire. Most notable improvement probably ends up going to Bugsy. That Scyther is now a mean bastard and can probably rip you apart even if his other two pokes are lolmetapod and lolkakuna. Pryce is still pretty lulz and Morty feels weaker than his GSC incarnation. The remaining others haven't changed all that much. Probably something like Claire > Whitney > Jasmine > Bugsy > Morty > Falkner > Chuck > Pryce for me.
The E4 is weird. Some of them are pretty bad, but others are pretty nasty once they get going. Wil and Bruno notably aren't too impressive. Most of Will's pokes are slow, and their dual typing lets you pounce on that even if you don't have a dark type. While Bruno has learnt to deal with flyers, but still dies horribly to a single Psychic poke. Koga gets pretty nasty if you let him pull off any of his combos, but thankfully half his team is weak to FIRE (gogo Choice Scarf Arcanine). Karen's only notable poke is her Houndoom. Nasty plot on that thing = hey kill me in a hit or two because I WILL fuck you up otherwise. The Umbreon is annoying, but Umbreon offense and Gengar is decent otherwise. Lance...I dunno. I got pretty lucky since all 5 shots of Blizzard hit and his lowered levelled ones got one-shotted without problem. Outrage on the level 50 one though is nasty shit. The Aerodactyl is probably his second biggest threat, but getting the ability to set up on Charizard with Feraligatr made it easy to handle.
Pokes used/Final team:
Feraligatr: Used this instead of Typhlosion because a) Water and b) Different pace from using Cyndaquil typically in GSC. Mmm...I think Gate sums it up pretty well. The Gen 4 Physical/Special change, Gator is the one who ends up benefitting significantly. Running Ice Fang/Crunch/Agility/Waterfall made it plenty scary and got plenty of coverage across the board. It also learns its moves in good pacing for upgrades so it never has really any notable amount of lag. Probably MVP overall of the team.
Ampharos: Yeah, I used this thing in GSC. In HGSS, I think the only really notable thing I can think of is that it picks up Discharge on its own. So you don't have to waste coins/TMs on it to give it a stronger Electric move rather than Thundershock. Otherwise, its pretty adequate for the main game. A little slow, but very meaty SpA means it deals plenty of damage even on things that are neutral. TWave rounds out the package for slowing down big threats. Pretty solid overall
Crobat: Wasn't part of the final E4 team due to it being underlevelled, but you know what to expect by now. Horrible horrible failure while as Zubat until it learns Bite. Then it starts getting better with Wing Attack and eventually evolving. The big thing with Zubat though is that if you've been using it regularly, it only takes like 1 or 2 more levels after it becomes Golbat to evolve again. And THAT is a huge power surge, especially since that happens around midgame. Very good when is around though and wins primarily through chippage means.
Arcanine: Ew. I wanted a Fire poke and I always told myself I should give this thing a try since I typically just run Typhlosion. Well okay, so what does it have? It learns pretty decent moves so it gets a solid variety and it stat bases aren't horrible. Flip side, it takes too long to learn the good stuff, stops learning moves after evo, so you can't fast evolve it and even after evolution it isn't performing much better than anyone else since most of them have reached Tier 3 by then too. In short, it's not a good investment - Vulpix > it in-game anyway.
Clefable: Heh. I picked this up in the Safari zone and then just EXP shared it to hell and back, learnt Meteor Mash and then evolved it. In retrospect I probably didn't need to since the end moveset didn't really justify Meteor Mash. Has its usual good points of being a good shoe in since it can learn many different TM abilities. In my case, it got Blizzard, which made it a decent switch option against Lance's Dragonites which either pack Thunder or Blizzard or something pretty nasty. It's relatively tanky too, which allowed it to survive a Dragonite Outrage (with like 5 HP left albeit), and eventually come back with Cosmic Power + Blizzarding those things to death. Very small time period of performance, but pretty good when it was there.
Espeon: STAB Return with Adaptability = Around a 200 powered move when Return is at full power. Jesus christ, that was nuts. Running around with a portable SelfDestruct and knocking things out in one go without trouble was pretty lulz. I did eventually evolve it after learning Baton Pass - and then found out that there wasn't much it could pass and the after game is more raeg then the other Pokemon version >.>. As Espeon, it performs solidly. I could've used a stronger move than Psybeam, but that was enough to hold down plenty of threats for a while. Only the E4 pokes were able to take two on a SE, and they would've died if I had Choice Spec'd it. Probably third most valuable member after Amphy
Butterfree: Eventually got dropped, but is surprisingly solid. Compound Eyes really does help it since it can status things with good accuacy and then proceed to win via chipping. The low stat bases make it pretty hard to keep on using it though.
Pidgeotto: Also got dropped, except earlier. It's notably worse in later gens sice Crobat is worth fielding often which means, you would want to get Zubat to level up and as a result, Pidgeotto gets less levels. It also takes a while for it to reach stage 3, so I can't imagine it being that overly impressive anyway.
Ho-oh: I used it against only 1 pokemon, and that was Karen's Umbreon so it can't pull off its annoying shinaningans. All I can really say is STAB Brave Bird. Ow. With no EVs and default level, that's still strong enough to high 2HKO Umbreon o_o.