I gather that there is a lot of disquiet with the DNC.

Well, yes, their not so hot on some things.

The Democratic party as a whole, for many years now, has been an umbrella party for the we’re-not-Republicans this or that niche group.

I have long lamented the lack of ideology, stated ideology, for the Democratic Party.

I think I understand why - there is probably no cohesive ideology for a group that tries to embrace atheists and (socially liberal) evangelicals, or old-time labor groups and free-market folk. Conceptually such groupings of people do not belong together, but find themselves in 2018 all opposing the hatred of Trump.