Representation in politics

In light of the news that the three main leaders are to hold a debate on getting more ethnic minorities, women and the disabled into politics, i'd like to add this rant:

I went to a recent Fabian event, which was well attended by ethnic minorities and women.

However, while I may be white, I was in a significant minority in that I wasn't posh i.e. public school, Oxbridge etc.
This is something that I think needs to be addressed. Now that ethnic minorities are being represented higher up the class ladder, how about some of us who aren't in the elite class being represented as well?
This, to me, is another key point when talking about proper representation that is too rarely addressed.

Skin colour should not be the only point of representation, so having women and the disabled up there is right. But what about us who come from outside of the traditional elite class? There are serious issues with the white working class feeling alienated from politics, and it's hardly surprising when all the leaders are posh and from the same circles, given the odd exception which does NOT disprove the rule.
I'm white and lower-middle class, although well educated with Degree and Masters by 22, but even I feel like the un-represented poor next to many of the people i've met in and around Labour, so i dread to think what the other parties are like