Short answer: No.
Long answer: NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO... there's already enough characters that have a near monopoly on power without any turnover without resorting to this...
Are there really too much power hogging? From my observations, there are more people with titles in general than without them, and I suspect they may even be more lords than non-lords. All I see, all the time, is a bunch of region elections going up with no one bothering to even utter a word to get elected, no candidate for75% of the referendum's duration, and then at the end only one candidate. Do these people really deserve a lordship? Not in my opinion.
I'm inclined to agree with Gustav, but to fancy Chenier's idea...
There would need to be a balancing effect, similar to estate efficiency, in that a lord of multiple regions has increasingly less effective production/control/morale/loyalty for each additional region, especially for highly populated or geographically larger regions.
Of course, there has to be something to discourage one guy being ruler, duke, and lord of all of the realm's regions and getting all of their taxes.
Isn't there a limit already to how many peasants an estate can represent, at least indirectly? One could go with a "a character may not have estates representing more than X population". I'd rather go with a near-limitless binomial system of diminishing returns, though, where one can get a bunch of regions but where estate efficiency lowers with population and area.
