Tikal is far, far more interesting than El Pilar. Indeed, El Pilar is not even the most interesting Maya site in Cayo -- that would be Xunantunich.
All the places you mention are great places to stay. Cayo District is a tremendous destination in itself, well worth up to a week or more for caving, seeing Maya sites, rainforest and mountain hiking, horseback riding, birding and other activities.
Besides the lodges you mention, which are expensive but worth it, I also recommend (among others) Ek 'Tun, duPlooy's, Five Sisters, Mopan River Resort (if you want a high-value all-inclusive) and, near Belmopan, Ian Anderson's, Banana Bank, Pook's Hill and Jaguar Paw.
--Lan Sluder
Belize First Guide to Mainland Belize
(288 pages, more than 75 photos and maps, available for $14.95 from Amazon.com)