Assuming that all UAs apply only to the capital and never to any other cities, maybe. Also UBs are generally more powerful than UAs, because you have to tech and build them. This is a National Wonder I suggested we put at Civil Service, remember.
The Great Galeass would go obsolete. It doesn't even matter if you balance it with that in mind, it FEELS bad.
Since when do GP improvements connect luxuries? If they do, then I have no problem with your Glassworks idea.
I'll repeat myself: Venice's UA is already balanced against itself. They get double trade routes at the cost of having to puppet all cities and not being able to found cities. Its also already balanced against the UU, since they can now expend Great Merchants to do nothing but buy a city they couldn't place or control themselves. In terms of power, they arguably have no UA or UU. A strong UB is not unreasonable. In fact, the current Doge's Palace is ~80% of all their power due to the amount of snowball it helps create. Keep in mind we are removing that and I am suggesting that we do not replace any part of that power until Civil Service!
Personally, I find all of the UBs you suggested weak to the point of being a waste of time. What do you have in mind for the Doge's Palace and when it unlocks? That might be where our discrepancy lies.
Edit: Also, what? +10 defense is impossible to conquer? The current Doge's Palace provides +6 in the Ancient Era, I'm suggesting +10 going into Renaissance. Doubled luxuries in one city is not that powerful because it may not even give you a monopoly, and all you have then is a few extra of the same luxury to trade. Double religion spread from only 1 city, in the civ that will not have their cities set up in a way that spreads easily (especially with the new spread mechanics), is not that powerful. +15% production in exactly one city, the ONLY city in which you can control what you build, is not overly powerful. The trade route effect provides marginal yields and can be acquired through many other means in-game. The massive production boost to naval units is not only highly situational but not even very good due to the inherent weaknesses of a large navy (can't swarm land where the cities are anyway). The GP improvement buff is also not super powerful because how many GP improvements are you fitting in that one city anyway? The only thing that's questionably powerful is the votes from shared religion, and coming up with a replacement isn't hard.
Now if you want to reduce the power on those buildings, then remove the GP improvement aspect, votes from CS, and +production on naval units. Does it look more reasonable now?