I lost game 1 of the Chesapeake Open on a tactical blunder. Two consecutive games now!
How to Improve at Tactics

Another loss due to tactical play that didn't turn out in my favor. Sometimes I wonder if the reason i play 1. d4 is because I'm a positional player or because I'm afraid of tactics.

Don't get too down on yourself. That probably doesn't help. If you have no tactics confidence you get afraid. 1630 tactics trainer is plenty for the 1200 USCF level. So possibly a lot of the issue is something else like seeing it in games like you mentioned. Did you not notice there was a tactic? Or did you realize but miscalculate?
Maybe take a look at your games and see what types of positions you are in when you lose tactically. What types of tactics? Were you looking for tactics at the time or did it come out of the blue? See if you notice any patterns.
In our game on move 22, Ne4 creates two weaknesses. It allows dxc5 leading to the weak c pawn which also completely opens the diagonal of the king. It's hard to calculate all of this through, but recognizing that the c5 pawn is pinnned to the queen and e4 is attacking it as well as realizing the potential weakness of the king on the a1-h8 diagonal is a signal to look for tactics. After move 24 black has a weak isolated pawn that is pinned to the queen. Black actually has an in-between move Bxf4 that prevents the fork, but bxc5 seems just as good. This led to a bad position where white can use the pin to his advantage tactically. That part didn't so much cost you the game but it hurt the position. If you didn't do that white never would have had that tactic. After b4 when you realized the pin was annoying it's important to look closely for tactics before playing Qb6. c4 seems to save black at least temporarily. You also have to be careful when your king is on an open diagonal, and probably check every move to see if your opponent can take advantage of it. The tactic isn't hard to miss, but there seems to be some key signals that one may be coming.

In my last ~50 hours with TT I've gone up maybe 40 points. I must be doing something wrong, I should be making more and faster progress.
It is going to take a lot more than 50 hours to improve on tactics. By-and-large, it seems to me that the Tactics Trainer ratings will be about 400 points higher than one's chess.com rating.

Hence it's a weakness of mine. My TT is only 45 points higher than my live standard rating. I'm also looking for tips, but maybe as you say I just need to put in more time

TT is artificial...Queens are almost always on the board...solutions usually involve checks. In the real world there are a multitude of game winning tactics that don't involve the queens or checks. My suggestions are:-
1.Buy the book "303 Tricky Chess Tactics" or something similar. It has practical real game positions that aren't too difficult to solve.
2. Go onto eBay and buy an old chess computer, Excalibur brand is good, and play lots of games at a low level. These things seldom miss basic tactics even on a low level. It's all about experience ;)

There are also a number of extremely strong computer engines available for free on any computer. Download a GUI like Arena 3.0 (the one I use) and you can download and install any engine you like. I usually use Rybka though sometimes Houdini 1.5a. (3142 elo) Even on an ordinary computer they should be stronger than even Magnus Carlsen. Especially with tactics. Which is much stronger than any player at our level needs anyway. Computers have different play-styles but tactics are concrete so they are extremely reliable.

I have had Fritz 12 for the last year or so. I use it for game analysis and opening training mostly.

Hence it's a weakness of mine. My TT is only 45 points higher than my live standard rating. I'm also looking for tips, but maybe as you say I just need to put in more time
I have the 2nd edition of this, it's up to the 4th edition now. If you want some combinations with more than a few moves of calculation like in Tactics Trainer take a look at it.
http://www.chessinformant.rs/encyclopedia-of-chess-combinations-4th-ed/
Me, too. Tactics Trainer has always had me too concerned about rating.