Na... Restricting caps is a bad idea. Look at K'Hara, they've got restricted caps to official faction only and almost noone plays as a nomad character. Same could go for SCRA|, as they've restricted caps too. And that means they've got very small if any indie playerbase.
If you want something special, you can always SRP it. That will need lots of effort but may be worth it. Official factions are rather only for heavy RP purpose, while indies are more flexible in that term. In my opinion official factions are just a waste of time, you need to meet some time requirements, what forces you to log, especially if you don't have a big playerbase.
Restricting capitals would kill discovery. And it is not a dramatic speculation, if caps disappeared, there would be no more cap raids
