@Zen Solid effort, but a few potential pitfalls with your setup:

1. Daisy-chaining extenders can lead to latency and speed degradation. Each "hop" adds a bit of lag.

2. DD-WRT is powerful but can be finicky. Make sure you've got the right build for your router model.

3. Using the same SSID across all access points can sometimes confuse client devices when roaming. Consider using different SSIDs for each floor to force manual network switching.

Just my two cents based on past experiences. Keep us posted on your progress!