Never. Ever. Buy. Standard. Variants. With. MC. ... Don't buy Champion variants either.
If you don't have the patience to deal with the grind, then I suggest purchasing mechs in packs. Mastery packs are a good way to go - they come with all the mechbays you need if I'm not mistaken, plus they get you a Hero mech. The Stalker bundle is indeed a very good deal. I would also recommend the Hunchback and Raven bundles as well. You could also purchase the Resistance package if any of those mechs suits your fancy. All four chassis in it are good actually, and you get lots of extra goodies to go along with it. (total of 16 mechs I think, all with mechbays)
Friends list. Yeah, it's clunky.
PGI... plz.
Too add somebody, you have to remember their name, click "Add friend" and type their name in. That's it. That's all it is. Incredibly simple, and incredibly dumb.
You can double click their name to start a chat with them, or click to open a menu and invite them to a group (if you have command of the group you're in)
CW!
Well, it's a long story. CW is great for farming a couple mechbays, since you get a free mechbay at Rank 2 in every single faction. So if you're new to the game, I'd recommend taking short contracts and faction-hopping. Try to get the free mechbay in as many as you can muster. Yes, you can do this completely by solo pugging, but... you will be canon fodder. As a new player, CW will be very rough and you'll be likely to be paired with or against large organised teams from time to time. You will get stomped, but you can at least get a taste for the CW game mode, the maps, and the free mechbays. The best you can do is to share with your team that you are new and ask them what you can be doing to be useful. Some teams will be more patient with you than others.
Aside from mechbay farming, I recommend
staying away from CW as a new player for all the reasons I said above: you'll get roflstomped repeatedly and it isn't fun, plus you'll be a liability to your team. The key to CW is to play with a group and to go into it with a solid and well thought-out dropdeck. The current Innersphere tonnage restriction is 240 tons (250 when facing against the Clans), so you'll need to own four mechs that come close to that limit without exceeding it. Don't start playing CW for real until you have four mechs owned and Elited in the Skill Tree. It will take months to get to this point, so have patience. If you don't know where to start... you can't go wrong with bringing three Thunderbolts to CW and filling the remaining tonnage with whatever you have that fits.
If you don't know where to start as far as eventually finding a home or group to play with, unit to join, or even which faction to choose, feel free to contact me. I know of several units in the FRR all with differing philosophies but all with very welcoming attitudes and very helpful veteran members - we could help you find one that fits.