Lanzarote is maybe a bit too quiet for you lot, I would have thought. Tenerife would be more the scene - Las Americas or Christianos. Have been in the Irish bars a few times in Lanzarote, but it's more of a chilled out place really for couples.
That's my opinion anyway. It all depends on what you are like as a crowd:
Max 5 or 6 pints, medium level noise, bed by 1-2 latest...Lanzarote.
Max 8 pints+, medium getting higher noise by 5th/6th pint, someone shouts "where's there a place open all night, and a bunch of women"....Tenerife!