It looks like the guild name formatting is the same as it was in GW1, in which case you pick both a full name and an acronym for the guild. RPS would obviously be the latter, the former I would be happy with Shiverpeaks personally.

As for beta burnout, I plan on avoiding it by limiting myself in the number of characters I play (most likely just the one) and I won't be playing a norn or a guardian, since that's going to be my main at launch and I don't want to spoil the profession or norn personal story for myself.