I just set up a Gen5 HT2000W modem and an Airport Extreme (similar to your Timecapsule.) The configuration I wound up with was much like yours, and has been working fine. I have two Airport Expresses on the LAN which are working well. One configuration I tried was attaching a gigabit ethernet switch to the HT2000W, and conncecting the AE, other computers, and printer to the switch. That seemed to work, but I didn't test it thoroughly. I didn't see any advantage over directly connecting the AE to the HT2000W and connecting the LAN to the the ethernet ports on the AE, as you are doing. I was having problems getting web sites to load until I made sure the "DNS Servers" in the Network System Preferences was set to 192.168.0.1 (the HT2000W). I'd suggest sticking with your current setup and tweak it if necessary to get things working better.
... View more