The default WebREPL address is not compatible with my network. Can I get it to start up with 10.0.0.129?
Look at webrepl,.html, about line 50.
The 8266 port is ok but it would also be nice to be able to change that.
It can be changed in the client webrepl.html at line 50 too, but you aöso have to change the call. When you start webrepl in boot.py, you can specify the port & password.
Can I specify the password too?
Yes, see above
Clear screen is something which has to be told by a script to the console. try at REPL: