All I carry is kydex. I dropped all of my hybrid holsters and never had anything leather. Kydex is rigid, consistent, protective. It won't wear over time and won't fold over into the trigger guard when trying to re-holster IWB. Not a problem if you take care of your holster and replace it when it comes time (it is a wear part if you use it long and hard enough).
Right now I do all my carry with a PHLster Spotlight matched to my Glock 19 and Streamlight TLR-7. It actually holds to the light rather than the gun so the combo is married so to speak. I'm alright with that. Also has space for a compensator and a red dot. Have a compensator now, might want a red dot one day.
I don't have a drawer full of holsters like some people but I've tried a couple I really like. PHLster, Bedder, BladeTech come to mind. Of course it's much easier to find molded holsters for any situation now that I'm carrying a Glock instead of my old CZ P01- great gun but about as non-standard as it gets.
As for SERPA, I'm going to advise you to stay away. Some people will argue with me all day about that, I'm not really interested. If they've done their research and they want to carry in a SERPA it's none of my business. But too many reputable instructors have found significant issues with their design, from encouraging negligent discharge to locking the gun permanently to the holster with the slightest debris, I will just recommend you avoid them until/unless you're very familiar with them and decide you want to carry one anyway.