The best rules to play are the ones you like and you have opponents to play against. Not very helpful but worth remembering.
I’ve not played CLA or T&T so can’t comment but if you have them I guess you know if you like them and they will work.
I believe I have read that StEA are a bit CLA-like so might be an updated better option if you liked CLA. The rule book and especially the supplements are great for ideas and pictures even if you don’t end up playing the rules. We played them a few times in the mid covid break and had fun. They are unit card based for activation so games with lots of units will slow down a bit.
Here’s my AAR but search for some of Ignatief’s fantastic AARs here to see more.
https://leadadventureforum.com/index.php?topic=126510.0Fistful of lead bigger Battles are lots of fun and very flexible. I like the playing card mechanic especially. Again it’s single unit activation, so keep unit numbers lower for faster games. The PDF rules are cheap for a taster. I’d get Bigger Battles for BoB level actions. The Core Rules or Reloaded would be for single figure unit skirmish games. Perfect for Osterns or the adventures of the Elusive Avengers.
We tried a small Men Who Would Be Kings game the other day and they worked pretty well. You’ll need to tag on some vehicle rules but that will be easy enough. These are IGOUGO with friction so should be faster for very big games. We’ve played some monster Sudan games with them okay. If you like these for Colonial actions or like Dan Mersey’s other rules they may be a good option.
Red Actions and Triumph of the Will are two more I haven’t played but looked okay from a read through. See Marks RA army lists and orbat data for inspiration and reasonable force compositions.