Personally, I love biothane.
Zilco tack is FABULOUS. I have a set in black, its so nice! Expensive, but it will last you forever! You want something where the bit can detach and leave you with a halter for when your at checks. Toklat Zilco Marathon Endurance Bridle and Specialty Bridles*|*EQUESTRIAN COLLECTIONS.COM
Or TO Zilco Deluxe Endurance Headstall and Specialty Bridles*|*EQUESTRIAN COLLECTIONS.COM
(which can be used in junction with a rope halter [regular ones are too thick] or the zilco halter, these I find personally to be easier than bit hangers, imho)
I personally do not like using fleece in unnessicary places... it holds alot of heat and gets nasty after a long ride. Where do you live? In cooler climates it may be ok, but I live/race on the east coast, its humid here! TO Zilco Deluxe Endur Breastplate and Breastplates*|*EQUESTRIAN COLLECTIONS.COM
That is the breastplate I use. One like this but without padding can work too, or even in nylon.
Tayloredtack.com is pricey, but her stuff is beautiful! She's a good friend of mine through races.
A simple rope halter/nylon headstall would work, something like this would be perfect. http://www.buytack.com/products/nylo.../23150-lrg.jpg
Its just easier than using a full bridle and switching every check. I wouldnt use a regular halter because I find them to be bulky and uncomfortable under a bridle, (not the zilco ones, though) and they're heavier.
Happy trails! Good luck!
Oh, and are you riding english or western?