I like the Reti idea. Play b3 to support c4 (and eventually d3), fianchetto both bishops and white has a pretty solid setup. I believe it's called the Anglo-Slav defense.
Need a positional, quiet and solid answer to the Slav
I'm also a Catalan player. My choice was 4.Nc3 e6 5.g3. White plays g3 in the semi-Slav often anyway so it's not much of a concession, and those sharp positions revolve around dynamics you want to practice in the Catalan anyway. If black doesn't take you can play 0-0 and b3 to reach a reasonable Catalan position.
I prefer something very similar: 4.g3. It often transposes, but in case black decides to take and defend the pawn, not having the knight developed early can be an advantage. On the other hand, black has the choice to go into what I consider to be (from white's view) a slightly improved version of the 4.e4 main lines, for example 4.g3 Bf5 5.Nc3 e6 6.Nh4, and (arguably I admit) having a pawn on g3 should be slightly better than having a pawn on e3.
If black takes on c4, this is not exactly safe and solid, but it's as positional as a system against the Slav can get.

Actually I think I'm more attracted to the Exchange Slav or the Slow Slav.
The Exchange Slav is perhaps more "solid, quiet, positional, safe and strategic". The Slow Slav is maybe more "sound and reliable" and objectively stronger. So it's tough to choose between the two of them...
Does the Exchange Slav give Black instant equality or does White still have some advantage?
Is the Slow Slav generally very "solid, quiet, positional, safe and strategic" or not?
Actually I think I'm more attracted to the Exchange Slav or the Slow Slav.
The Exchange Slav is perhaps more "solid, quiet, positional, safe and strategic". The Slow Slav is maybe more "sound and reliable" and objectively stronger. So it's tough to choose between the two of them...
Does the Exchange Slav give Black instant equality or does White still have some advantage?
Is the Slow Slav generally very "solid, quiet, positional, safe and strategic" or not?
There is no instant equality for black in the exchange Slav. Black has to be careful if white knows what he is doing. The Exchange Slav has a few interesting positional themes. That said, it is quite a concession to create a symmetrical structure and give black's knight the c6 square. Equalizing is certainly a more difficult task for black in any other serious line.

I play the exchange Slav, but it feels more like a King's Gambit than a slow slav. There are some extremely sharp variations. In the variation I play white controls the center but wastes time to do it, so black gets a lead in development. But I guess if you're satisfied with a draw you don't need to play for a win, so it could be quiet.

If Black goes with a French structure, you'll get this kind of slow, positional game, but if black had taken the e4 pawn immediately, the game becomes much more sharp and tactical.

The problem with the Exchange Slav is that I begin with 1. Nf3 d5 2. d4 Nf6 3. c4 c6, so if I play the Exchange Slav I wouldn't be able to play most of White's strongest options like 1. d4 d5 2. c4 c6 3. cxd5 cxd5 4. Nc3 Nf6 5. Bf4 Nc6 6. e3 Bf5 7. Qb3, that's why I'm fearing that if I play the Exchange Slav I would not get any advantage as White.
On the other hand the Slow Slav is more "main line" so if I'm not mistaken White fully keeps his first move advantage. And it also annoys Semi-Slav players as well as Chebanenko players because White gets many very strong options against 4...e6 and 4...a6 since he hasn't commited his Queen's Knight to c3.

Slow Slav with e3. It leads to the quiet positions you want. Just prepare a sideline against the semi-slav. Don't expect too much ...e6 at club level.

I'll work on it for you and get back to you. Give me 15-20 minutes. I have some ideas, but they might require looking deeper. There is a specific idea I have for you.
I've got it. I don't think the e3 slav gets any advantage, even though its very solid. BUT, there is also the exchange slav, which nets white a HUGE slight advantage. If he plays it right. Let's look at some lines.
Try it. Exchange slav with Qb3. You might just like it. It's not tactical, its hard for black. This is what you wanted right?

The problem with the Exchange Slav is that I begin with 1. Nf3 d5 2. d4 Nf6 3. c4 c6, so if I play the Exchange Slav I wouldn't be able to play most of White's strongest options like 1. d4 d5 2. c4 c6 3. cxd5 cxd5 4. Nc3 Nf6 5. Bf4 Nc6 6. e3 Bf5 7. Qb3, that's why I'm fearing that if I play the Exchange Slav I would not get any advantage as White.
On the other hand the Slow Slav is more "main line" so if I'm not mistaken White fully keeps his first move advantage. And it also annoys Semi-Slav players as well as Chebanenko players because White gets many very strong options against 4...e6 and 4...a6 since he hasn't commited his Queen's Knight to c3.
White needs to pawn on c4 or he has problems. You should consider "repairing" your repertoire by pushing c5 first. I'll give you an example of what happens with the pawn on c3. This is an actual game.

@Post 32 is it just me, or does Black hang his queen on move 8, with White refusing to capture it on move 9?

@Post 32 is it just me, or does Black hang his queen on move 8, with White refusing to capture it on move 9?
Ooops. I guess I'm still tired.

But clearly it's a sound plan. Qxb6 is a computer move that would never be found at "club level" therefore the variation is very sound.

I'm really scratching my head over one of the earlier posts.
What is a HUGE slight edge for white mean?
Inside joke. You only need a slight advantage to a win a chess game. Therefore, a huge slight advantage is a slight advantage that is enough to win.

Quiet and positional? What do you do against the open catalan crazy tactical lines haha? Its a good thing that at club level nobody knows that stuff.
Anyways, I play the 4. Qc2 line on ICC 5 min quite a bit. At around 1500-1800 rating range in 5 minute a lot of people just end up playing e6 and you can get your closed catalan with Nbd2+g3. People are lazy and the typical class B player will think they are setting up a Semi Slav.
Sometimes they do play g6 or dxc4 though but e6 is way more common. And plus, you can take the opponent into YOUR territory.

lolurspammed wrote:
So 0.5 is enough to force resignation?
Define 0.5. You have to remember that these computer numbers are arbitrary and have nothing to do with the actual position. They are set by chess experts and programmers, both of whom are human. But yes, any advantage is enough to win because any advantage will get bigger and bigger and bigger until it's too big to control.

https://www.youtube.com/watch?v=8Wd591R-bJI
GM Ipatov, former world junior champion was probably inspired by his trainer GM Grivas who has played the move several times, and has published a survey at a well-known chess magazine.
This is a very good choice for Catalan players.
Interesting--may be a more accurate way to get a catalan rather than Qc2. I'll have to look into it. Seems straightforward.
I'm also a Catalan player. My choice was 4.Nc3 e6 5.g3. White plays g3 in the semi-Slav often anyway so it's not much of a concession, and those sharp positions revolve around dynamics you want to practice in the Catalan anyway. If black doesn't take you can play 0-0 and b3 to reach a reasonable Catalan position.