Blisss can provide some party buffing, that was his role in another game, but it's not superpowered. He spams the buffs because he can cast his entire, very limited spell list every 5 minutes, more or less: 0th=2, 1st=2, 2nd=2, 3rd=2, 4th=1, I think is how it will work out, or near enough.
In a previous incarnation it was:
Mage Armor, +4 AC Force for all. Shield of Faith, +3 AC Deflection for himself and the big fighter.
Legion’s Conviction, +3 Saves Morale for all.
2xMass Snakes Swiftness, 1 extra attack for all, twice per encounter or 5 minutes.
That is all.
PS. Is there any use to this?
Or he could have some other role, he's the ultimate in spell and SLA flexibility – only a few different ones, and not high level, but within those constraints he can spam whatever we'd like them to be. He was also a healer in previous incarnations but this party seems like it won't need that from him either.
Suggestions, anyone?
PPS. His main role was info: Knowledge skills, lore, languages, magic, and a chance of hearing practically any story from anywhere/anywhen. The DM's infodump dream. And working with water and ice... that could turn out to be unusually useful in a Frozen Night.