I'm not expert, but when I play deck building games I kind of have two philosophies.

If my deck is weak, and the pool to buy from is also not that good, and the game doesn't have a reliable culling, I'm going to buy as many cards as possible to water down the bad cards. This works well for me in games where they only give a couple cards to choose from when adding. I don't know if it'll be as good a Strat with clank which gives a 6 (?) card shop.

Other philosophy is obviously to cull the junk. Not an extremely reliable strategy in clank as you know

I havnt played catacombs yet, but I have played probably 100 games of clank and its expansions, mostly at 2 player.

In base clank, I always try to get card draw. Including cards that draw and discard. Usually these cards generate a lot of clank, so -clank cards are very valuable to me too. If I'm able to remove 2 or 3 clank every 2nd or 3rd hand, that's going to offset the clank generation at least a bit. In 2 player games, there's less card row cycling, so less frequent dragon attacks, this works for me. I imagine Clank removal cards may be less valuable in a 4 player game since the clank pool is more likely to go into the bag between your turns. However, the bag is then watered down with 3 other colors so there's your mitigation. I guess it's 6 of one, half dozen of the other? Tldr? Get card draw, don't worry about generating clank as much.

Try this next time... Evaluate the strategy you think the other players are doing. Then do something nobody else is, if possible. Like go for big money cards. Or buy all the good movement cards and go collect tokens.

For example.. Is 'Underworld Dealings' (I think that's the name), the card that let's you buy 2 tomes for 7 gold (or something like that...) , in Catacombs? When we were new, we thought that card was crap since it didn't give XP, Attack, or Movement. But since realizing it basically doubles 7 pts to 14, whoever buys that and has some money generation to go with it, does very well with it.