Doesn't matter what you perceive that you need as you already have most of it in reality (it matters what you have). The P660R is a Router and a ADSL2+ Modem in one device. You have turned off the Router function in the ZyXEL by placing it into Bridge Mode, but that does not remove the fact that it is still a "2 in 1" device with a Router and ADSL2+ Modem.
The ZyXEL already meets 3 of your 5 wishes (not needs).
1) ADSL2+ subjective) better than the one I have right now 2) can be set to bridge mode subjective) 1000 Mbps WAN output 3) cheap (will be using it for a year only)
The P660R is already ADSL2+, it is already set to Bridge Mode, and it is a cheap as it possibly gets as you already have it.
