New speakers or new tubes

I am running a Prima Luna Dialouge HP into Thiel 1.5s with a Rythmik 12 inch sub in a fairly large room with a vaulted ceiling. One of the features I like on the Prima Luna is the ultralinear/triode option.I first heard this ption on a Manley amp years ago that I couldn't afford but then saw it on the Prima Luna and I like changing it up. When I first brought home the amp I was using Tekton Lores with an efficiency in the upper 90s and the switch from ultralinear to triode was very apparent and enjoyable. At the time my Thiels were in the basement with blown tweeters. I decided to have them rebuilt by Rob at Coherent Sound and when they came home I put them in the system and decided I prefer them to the Tekton Lores. The Tekton has better bass, which was addressed with adding a  subwoofer to the Theils, and bigger soundstage but the Thiels are so smooth to my ears in the midrange it's overall more enjoyable to listen to. However, maybe due to the lower efficiency of the Thiels, they don't sound great in triode mode. When the sound mellows out as it does in that mode it is now too flat and lifeless, whereas with the Tekton it was relaxed but still had dynamics, soundstage, etc. 

My question is, if I'm going to make a change do I roll bigger tubes, KT 120s work in this amp, for higher watts, would go from 70 to 90 ultralinear and from 40 to 50 in triode, or do I look for a high efficient new speaker, perhaps bookshelf, that bring me the great midrange of the Thiels, the enjoyable sound of triode mode from the amp and perhaps a bigger soundstage than the Theils, more like the Tektons. Thanks for your thoughts.