Free2Play arena shooter games that are skill based.
Battleborn.
It's a skill based arena shooter that requires players to work together to complete goals within an arena of waves of PvE combat.
You deal with both flying and non-flying characters that have both AOE and non-AOE attacks.
Maps are large.
http://store.steampowered.com/app/394230/Battleborn/
Paladins
http://store.steampowered.com/app/444090/Paladins/
Same as above except the maps are smaller, the characters are beefier and while there is comparisons to Overwatch from trolls, it's really more similar to Team Fortress 2.
Team Fortress 2
It's skill based. People with high skill can wreck people that have the best unique gear.
Arena shooters game that is skill based and have flight in it and that you have to pay for.
Titanfall 2.
It's MP can be additive as you get more skilled which isn't hard to do.
https://gfycat.com/AromaticGrimDuckbillcat
https://gfycat.com/GlossyCreepyGuineapig
All the weapons in the game is now viable options. There has quite a few updates.
Some weapons are hitscans and some are projectiles. Both types is usable.
Once you learn to fly, you never stop trying to get better at it. Once you learn to fly + kill, then it gets truly addictive.
Overwatch.
It's TF2 + Disney characters + small maps.