It's certainly true that the dev board has some non-ideal qualities - and the 2.00mm pitch headers make it hard to work with - but everyone's got to start somewhere. If you haven't looked at it yet, check out the WiFiMCU dev doard by DoIT -- check out the other forum posts for more details on it - it's definitely a more user-friendly platform to work with.
As for the antenna position - it's mounted hanging off the board for improved RF performance, not for space/size reasons. Optimal radio performance i achieved when there's no copper / metal near the antenna. In situations where the module (antenna) cannot be mounted in the exact corner of the host PCB, it's common practice to hang it over the edge. In this regard, I'd actually say this is a positive feature of eval board that they considered WiFI performance.