If by 'budget-conscious' you mean more along the line of motels, short stays, and no need for major "frills" I would recommend Choice Hotels.

They have a huge presence, over 6,000 locations, and are going to be coming out with a new credit card in July which should help accrue lots of points. They also have a nice range of partners to get points with (or transfer points to).

If you want something a bit better in terms of amenities, higher quality locations, etc, Priority Club might be the way to go. They have a good blend of budget places (HI Express, etc), as well as mid-range stuff like regular HI, and you can then redeem points for their higher end product like Intercontinental and Crowne Plaza's.

As for Hyatt, SPG, etc you might be a bit hard pressed to find rates regularly under $100/night.