Honestly, some of those questions are hard to answer. A lot of the answer depends on how long you've been gone and what level you were playing at. I'll admit to not being a max player, (FTP here) but there have been a few improvements and a few setbacks.
I personally love Killshot and use him all the time. Panther is hit or miss for me. I love the power of the shield, but as a sniper, the coloring can mess with my aim. Surge is still awesome and Bastion is the biggest pain the butt on the block (too much hp and it still has a shield on top of that!!). DL's are still exceedingly powerful, EM's are still powerful, but I don't fear them like I did 9 months ago.
I don't consider myself high enough for the Meta, so I can't really say much.
I think the progress path being good or not depends on what your goals are as a player. If you want to get the biggest, best stuff as fast a possible without unneccesarily spending, its probably not for you. But it has made more stuff available without spending real money and made it easier for FTP people to play the game. Its not perfect, but I personally think its better than what we had.
My advice: If you're FTP: plan out a path to get what you want and then stick to it - save those A-Coins! If you're PTW, check out the reviews of the legendary weapons and mechs on the youtube channels for people like Scape211, Mayer, and others and buys some good stuff.
Oh, one last thing, bots are much more agressive. I've lost to them more lately than ever before. I wouldn't worry about if you're going against live players or bots so much as how much fun did you have in the match.
Anyway, that's all I've got. Good luck!!!!!!!