The thing about a lot of polls, is that if they are really valuable, one way or another, the campaigns will not release them (if they’re commissioned by a campaign) or will buy them up so they aren’t released. There’s a reason why most internal polling is never formally released and just hinted at - campaigns don’t want to help the opposition. Campaigns, PACs, various political organizations do release polling data that is meant to either motivate their people to get out and vote, or to depress voter turnout with the opposition, and I wonder if that’s why it seems like here have been more Republican polls than Dem polls released.
I’ve got a friend at a private analytics company here in Austin (they used to do a lot of polling but now they mostly measure other metrics) and most of what they develop for various campaigns and politicians will never see the light of day, even though it would surprise/interest a lot of people.