Warmane compared to other options for BG's

Good evening everyone!

Before anything, I want to say that I have done my fair bit of research and am only reaching out because I haven't found a direct response. I know I might get some bias responses but I don't have another option. And if there is something I've overlooked, please be nice :o

I'm in a bit of a dilemma here. I want to start on a server, but I'm wondering where I would fit in better. Yes, pve is important to me but I want to invest in a server where my progress would be viable in pvp along the way.

I know Warmane is a little bit on the "donate and have it easier" side but how possible is it to be competitive if I do not want to pay for my gear? I'm interested in both Lordaeron and Frostmourne. What is the difference between the two when crossrealming in battlegrounds? I understand there are gear score brackets, do these apply to both Lordaeron and Frostmourne? What are the range of the brackets? Are they basically active end-game only? Estimated queue times? Feel free to put in any other input in regards to these two.

Thank you!