Wow did you really have the wrong natures the whole time?
Anyways the only really common problem this team has is Jellicent. If it switches in on 1 layer of t-spikes as not to be fully poisoned it be really be bad news for this team. It also stops Tenta from spinning easily which can really put you at a disadvantage against other stall teams that have Jellicent as their spinner. I don't see it costing you every game but things like Politoed and Ferrothorn who don't have the completely reliable recovery could be in trouble. Really not much to change, but you might want to consider running something like Wish Jirachi with Thunder and maybe calm mind to really give you an advantage against those teams since Quag counters other Jirachi. It might also help against Virizion and Reuniclus alot if you run psyshock. It could run a calm nature and wish to still do the things Chansey did.
Also, just curious, where does the name IR come from?