Revogirl started a poll a little while back (LINK) to see who enjoyed which Revomaze design the most, and the Bronze was voted highest, with Blue and Orange second. This isn't surprising since the Bronze is a great puzzle, but also it's been around longer, so more of us have likely solved it. I never did get around to solving Indigo, but Orange is also a brilliant dynamic maze that I very much enjoyed solving!
BluOb: Open (30/10/10) GrOb: Open (01/11/10) BlOb: Open (04/11/10) ROb: ... BluEx: Open (27/01/11) BrEx: Open (09/02/11) REx: Open (17/04/11) OrEx: Open (20/07/12) CuEx: In progress
Revo Mini: Open (05/07/13)
I guess Gunmetal and Mint also fall into the category you mentioned, Ozzy, even though Gunmetal is not a general favorite...
My top three currently is:
1. SILVER
2. LIME
3. INDIGO
Open: BU, BU Obs, PRO, BR, IN, GR, GR Obs, MT SE, GM, TI, LM, OR, BL Obs, AU, AQ, AG
In progress: CU
Closed: R Obs
Waiting for: MT V1, SL
Wishlist: R, PU, BL, MINI