If you're not trading anyone, Geodude, Abra, and Slowpoke will have very limited uses late game. I've always liked hoppip but with your water and electric pokemon, you won't be needing a grass one. Nidoqueen could be cool to have late game. I would probably exchange a rattata for the nido.

B) Switch out Rattata for Nidoran Female. (I don't see Raticate doing much for you when you have such better options late game. I could be wrong, though! I've never given the light of day to Normal type pokemon.)

I think you should continue a little further with your current party, just to see the pokemon that you can capture on later routes. At the moment, you've got a few pokemon that will get tough later on due to trade-evolutions (although that's all part of the challenge :D), but before replacing some of your weaker ones (rattata, maybe beedrill), it's worth seeing if they'll actually be replaced with something worthwhile xD Otherwise I'd just continue with the same team

It depends if trading is available or not. If it is, Gengar and Alakazam can be great team members.

Abra and Hoppip should go to the daycare no matter what, they can't do anything now.

Keep Rattata until you get a better (in the long run) normal pokemon for Morty.

Croconaw, Flaaffy and Zubat are solid party members. If trading isn't available Nidoran Female and Slowpoke are your better options to complete the team.

I'm going to trade pokemon to another game, then back. So the trade pokemon will for sure get better.

Well that makes some of the decisions a bit easier at least

It's on a 3DS.

Okay, trading mixes things up a bit.

1) Slowking or Alakazam? If you're tired of the easy pick Ala, and want something fresh, pull out that Slowking! It'd be a bit redundant, however, since you have a great water type already. Hmm.. Maybe you won't even need a psychic type pokemon if you plan on picking up a flying type.

2) Golem - Can counter electric types, which your team lacks a punch against, and can somewhat counter ice pokemon, although his own weakness to them is a problem. I wouldn't use him, wait and hope you get a swinub!

3) If you plan on getting the Eeve, get an umbreon. You need something to counter psychic and ghost type pokemon more reliably than Gengar (i've always regretted his dual poison type.. :(   )

Right now I'd go like this:

C: Take out Beedrill and Rattata. Trade in Abra/Slowpoke and Nidoran Female for now.

I am, but that's only because there is a viable way of emulating GB, GBC, and GBA games. There is no great DS emulator.

I guess I'm one of Moon's benchwarmers...

LOL. You are one of my party's top 2 pokemon.