urghh don't pick stuff just to be different or want to try something 'out of the box'; i support using esoteric sets, provided they are actually fit for the team.
also furai told me to post here about how i think eleceus > iceus, so here goes:
iceus' only boon is that it has a stronger stab ice attack, but apart from that it suffers from an sr weak, only 1 resistance, a plethora of common weaknesses, and the requirement of abomasnow to use its stronger attack (blizzard).
eleceus only has one weakness, most commonly seen in groudon / rayquaza, both of whom are outsped and ohko'd at + 1 (252/0 groudon takes 79.2% - 93.6%, so a bit of residual is required, but it doesn't ohko with 4 attack eq anyway).
garchomp, excadrill, groundceus are all quite rare, they do, however, beat eleceus (exca needs LO and sand up, groundceus needs to win the speed tie once, scarfchomp only deals 74% - 87.1% to 4/0 arceus with EQ).
Ekiller with eq is a good check, however, but with rain support risks taking massive damage from thunder, and paralysis.
Darkrai is probably the best check, outspeeding and dark void hitting 80% of the time, but this is a common CM arceus check anyway.
with rain support cm eleceus' + 1 thunders are immensely powerful, achieving almost perfect boltbeam coverage as well, with only the practically non-existent rotom-h, rotom-f, lanturn, shedinja and magneton/zone resisting it.
so yeah, eleceus > iceus unless you're running dedicated hail in ubers.
ferrothorn is a pain for both of them though.
1. Ekiller arceus, deo-a's set can beat its most common checks and counters (although it IS outsped by scarf terrakion), at any rate lugia is destroyed by thunder (which it can't roost stall) and giratina takes 80% ish from psycho boost, paving the way for ekiller to sweep later in the game.
2. Darkrai, covers all CM arceus that set up on -2 deo-a and is a fantastic wallbreaking partner, use the sub / pulse / fblast / dvoid set.
3. DD Rayquaza with overheat, breaks down the common stall set up if it can lure ferro/skarm into taking overheat, then just outrages until it dies; make sure you don't do anything if scarfpalkia is still alive, however. DDQuaza + Deo-a can make a win condition all by themselves, since a team cannot continually stand up to their assault assuming the player isn't stupid.