Does Such an Opening Exist?

Chess openings are diverse. Just when it seems there is nothing else to explore, something is found! I recently decided to experiment with the Nimzowitch defence for Black and really like its lines, plus the fact that it is unusual and thus psychologically intimidating. I know I am supposed to have an advantage as white but really the only 2 tactical openings that White can choose are Spanish and Italian Games. Is there any else? Maybe a set of lines where I can start with 1. Nf3 or 1. c4 and always have a tactical opening to transpose to? I do not mind that these lines may be slightly lower win % but as long as they are sound, and give at least a slight plus score with best play that's perfect.

So you want something that's got a solid pawn structure, but not super-positional?  For White the Catalan might be good, perhaps via Nf3/c4 so you can transpose around?  For Black maybe try the French against e4 and possibly the Semi-Slav or Nimzo/Queen's Indian vs d4?

The Catalan is a good suggestion - its base is d4-c4, so you can revert to mainline 1.d4 theory in any position where the Catalan setup isn't helping you. You can also use the setup very well against flank openings - Benoni and Dutch - which aren't very common. 

With black, you can play the "caro-slav" structure which plays the Caro-Kan against e4 and the Slav against d4. The structure is very similar, so some ideas in these openings are interchangeable (early c6, the Bf5 - e6 theme, the queenside advance).

I think this is a good repertoire choice if the idea is to reach some kind of relatively equal middlegame that isn't horrifically sharp. 

Ok so first of all, thanks everyone for your quick responses! Now maybe I worded this the wrong way, but I meant that I DO like tactical openings, and the more tactical the better. When I said I wanted to avoid super-positional games, I would really like to make the game as tactical as possible. Now of course I know that's not always possible and I've been working on my strategic play as well, but I would like a set of openings that can remain fairly tactical With that in mind, then, these are great suggestions by themselves but give Black too much choice IMO. Let's say I play 1.d4. If they play ...Nf6 and then go for KID or QID/NID, I can play the Torre or Catalan. But if they play ...d5 on their first move I am stuck in a positional game! What I was looking for was a comprehensive set of responses that can be tactical in each possibility. Maybe if there is a response to d5? Also are there any examples of a GM or IM who plays d4 but treats the positions tactically? If so maybe I can refer to their games

Aronian and Topalov. For instance, the games from the 2006 match between Kramnik and Topalov offer many good examples of how to play aggressively against the Slav.

Sounds like you should be going for main lines in Queen Pawn openings.

I know you say No Gambits (but follow up with "unsound"), but I hope you don't truly consider the "Queen's Gambit" a gambit.

1) The Grunfeld is tactical in its own right.

2) There are many agressive lines against he King's Indian that are also sound, like the Saemisch Variation (5.f3)

3) There is a line in the Queen's Indian where White plays an early d5 that is extremely wild that White can go into.  (i.e. In response to 1...Nf6 and 2...e6, you'd play 3.Nf3, which can lead to a QGD, QID, or Bogo, and the QGD line doesn't disrupt the line below - you can still transpose straight into it).

4) The Modern Benoni is tactical in its own right.

5) If you study the theory of the Fianchetto Variation or the King Walk Variation, you can assure yourself a clear advantage in the Benko Gambit.  Its popularity is based on intimidation, not soundness.

6) Against 1...d5, there are plenty of lines where you can avoid "super-positional" lines:

• Against the Semi-Slav, play the 5.Bg5, leading to either a Botvinnik, or after 5...h6, play the Anti-Moscow (6.Bh4)
• Against the Slav, the 4.Qc2 lines are sound and not as dull as the main line Slav
• Against the QGD, play the Rubinstein Variation (1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.Bg5 Be7 5.e3 O-O 6.Nf3 Nbd7 7.Qc2 - Instead of 7.Rc1 - where Black must play actively with 7...c5, after which White has a choice of whether to take a high risk with 8.O-O-O and go for the race or 8.Rd1, but after any other move, like 7...c6, which is way too slow for Black, 8.O-O-O and any ...h6 push, before you automatically move, always calculate whether an h4 response works or not.
• Against the QGA, the 3.e4 lines are pretty agressive, yet sound for White.

Again, the "Queen's Gambit" isn't really a genuine Gambit, so it shouldn't be eliminated by your No Gambits clause.

These are very good. I dismissed 1. d4 at first and play e4 but heard that Aronian for example "plays 1. d4 but plays the positions like e4". I like the line in Topalov-Kramnik above. Maybe to give an idea of my play style I posted three recent victories. This might help indicate what I like to do?

BTW, yes, I am fine with Queen's Gambit. It's not really a gambit. And I want to give it another shot. I also like Catalan, although Black gets the choice whether to play Open or Closed I think? Not a huge fan of Torre or London. Colle looks ok but I'll try this first. And as I said, for Black I like to play KID or QID (still experimenting) to d4 and Nimzowitch to e4.Big shoutout to Synaphai though for giving me players to study. That is very helpful

I don't agree with all these people recommending the Catalan. It is so positional and so slow that the ideas are hard for class players to understand. It is almost the most positional opening there is, and it's neither conducive to improvement nor what you want. However, there are other queen pawn openings, some of which were mentioned by ThrillerFan, which may be more up your alley.

I also think it's important to point out that chess openings - despite their various tendencies - aren't ever just one thing. The Najdorf is well known for its sharpness, but huge numbers of Najdorfs are decided in technical endgames (an exchange versus two bishops, for example) because the pieces fall off the board all at once during the tactical phase. 

Also, I want to mention Valentina Gunina - she's a very gifted tactical player who plays 1.d4, the Caro Kan, and the Slav....which is not to say that you should choose these, but it is to say that a tactical player can still flourish in positions that chess books might call 'safe' or 'boring'. Something I've found very helpful is developing a 'council' of specific great players that I consult when I hit a wall in my repertoire - Petrosian, Kramnik, and Karpov will show me a selection of safe ways to play that I choose from according to personal taste. Korchnoi and Morozevich will show me novelties which I put in my back pocket for later. 

Tactical players who play 1.d4 off the top of my head are: Korchnoi, Morozevich, Kasparov, Mamedyarev, Ivanchuk, and I believe Maxime Vachier-Lagrave also plays the occasional d4.

I'll throw in Bird's (1. f5).

It may not be as tactical as the OP desires, but when played as a reversed Dutch Stonewall, it has a solid pawn structure and lends itself to kingside attacks. It's also unusual, which the OP appreciates.

I don't see the merits of the Catalan for the OP. It's way too slippery and positional for his specs.