1. fully agree, will love too that mc is actualy doing some real work :) and have some traits, which he can gain and lose. and having to defend own mansion sound extremly interesing..especialy if you defeat and capture robers, see my point 2 :)
2. yeah, thats excelent idea, will love more that mc have to work on himself before he can work on others...and it opens some other posibilities..like he will devolve to dark magic to "steal" knowlenge (aka skill points) from other persons, which will kill them in prosess. so your mansion will be in time known as "hotel californian" - place in which you go in, but will never leave.
3. fully agree with selfcasting on yourself inside mansion, it will save a lot - goiung out and then in.