I also use the system from Rolemaster Companion II. It is the best system I have seen so far, except maybe the one used in RMFRP/RMSS.
Similar skills is a brilliant move, although a bit tough on the book keeping and definately not for beginner players in my opinion. Once you have it going it works very well, and nothing prevents you from removing and adding similarities.
The extended level bonus table is also used in my campaigns, but they are usually quite high powered.
I give 20-30 percent extra development points to characters to use on secondary skills.