Wow, I really like it! Your skills at JK editing have improved tremendously since I saw your last work. If you keep up this creative streak, I'd reccommend you release it. I especially kike what good use you've made of th Baron's Hed Texture set, it seems to fit very appropriately.
Now for some suggestions:
1) Perhaps a little bit to neat. I know it's still in the early stages, but a few more sloped wall faces, or some cracks and crannies in the walls, ceiling, maybe fallen debris, could add a lot. I assume you're going for an ancient, forgotten monastary kind of look (I could be wrong). THis brings me to my next comment.
2) The first thing that came to my mind when I saw the title of this thread was the
Shambala Santuary from
Indiana Jones and the Infernal Machine. That was a great level, and if you have the game, I'd reccommend you'd play through it for ideas (especially seeing as both JK and TIM use virtually the smae engine. Several things I'd recommend adding off the top of my head: a candelabra 3do in certain rooms (I think there's a 3do on Massassi), an outdoor area with snow, stain-glass windows, and an altar and some pews.
3) The lighting is good and I like that wooden trellis you made. I would reccomend you darken the level overall slightly, and have something hanging from each beam of the trellis, whether it be a candelabra (as stated above) or a small paper mesh ornament or candilier.
4) I don't know what other rooms you have in mind, but perhaps Google "sanctuary" or "monastary" for ideas in how to implement further rooms/designs.
I really like where this is going. Keep up the good work, and get this baby released sometime!