Best mod sites/help

What exactly are you looking for if crouching rancor isn't helping you?

As general advice, don't slice mods that don't have good speed. Except for some specific set/primary combos, I don’t even keep mods that aren't at least 10 speed at gold. Typically I don't slice mods to 6 dots unless they are at least in the high teens...it can be a little more relaxed now that you can slice 6 dots further but I still wouldn't be comfortable risking that.

As for relics, don't over do it. Characters can perform at lower relic levels (or even g12) if you have good mods. You really only need high relics on GLs and their requirements, some pilots, or Cpit raid characters. Some other really good characters can warrant it, but in general you want to keep relic levels low unless you are going for a GL or need someone for Cpit.

Without seeing your mods it is highly likely you fell into the most common pitfall. Which is worrying about set and primary. Crouching Rancor does a good job here. And while those are important it should come with the caveat of "if speed is equal" to a different set of mods.

Ahnaldt101 has a good video on this in terms of slicing guidelines and general efficiency in terms of working on mods.

If you look at your best characters stats and the blue number beside speed (what comes from your mod bonuses) is under 100 you are prioritizing the wrong stats on your mods.