Actually I prefer Ice punch. Basically just because it can freeze..
Have a nice day.
Hm, never saw your reply until now, Hip. And to give a reply to that, I'd rather still go with ThunderPunch over Ice Punch mainly because ThunderPunch can go over Thunder Wave if you want a more offensive Alakazam.
With ThunderPunch having a 10% chance to paralyze something, it's still worth considering and to also 3HKO the Psychic-/Water-type Pokemon who laugh at 'kazam's unresisted STAB Psychic (but it becomes neutral due to +STAB -resistance, clearly) and having a slight chance to paralyze them as well during the 3HKO process (only if they're at full health, that is).
The 10% chance to freeze also sounds nice, so Ice Punch is still worth the consideration. It's really up to the user if s/he wants to give it a fun twist to Alakazam and have a surprise factor on it and use either ThunderPunch or Ice Punch on the opponents Pokemon. Or if they for some reason go all-out offensive late game sweeper Alakazam, I suppose it can have a Abra-Pokemon-Stadium moveset: Psychic, ThunderPunch, Ice Punch, Recover/Seismic Toss.
The damage formula is very similar if not the same. but I don't know how the catch formula is
And one question. Can ice-types get frozen in RBY?
I would believe they can. There is no true Ice-type in RBY. They all have an extra type, which is mainly all Water, other than Articuno and Jynx who have Flying-type and Psychic-type with their Ice-type. (I think if there was a true Ice-type Pokemon, maybe it wouldn't be able to freeze, but that's just a what-if/what-could happen thing, since it doesn't exist.)
I can't confirm that I've seen them being frozen, but when I use to play Stadium as a kid, I remember freezing both of those Pokemon. I also have frozen a Cloyster once when battling on NBS. So, if I could freeze those Ice-type Pokemon, then I'm sure the others can freeze as well.
~ Aether Nexus