Help with what type of troops to train

My main troop type are fighters. I have just under 2 million T10 fighters with 265,000 troop size and over 2 million T1 taxis. I have a little over 200 million true might.

So my question is with the training bonus in effect what should I train more of? I've heard of people training a bunch of low level troops for a meat shield but I'm not sure which and why. I don't really get attacked anymore but I do attack sometimes during VC. Any help is appreciated thank you.