you can get phone verified accounts from a provider, they generally know what they are doing, if you're going to use the accounts to promote the same thing i'd say you go for 1 proxy for 1 account, if you're going to use them to promote different things you are safe with up to 4 per ip. Make them look as natural as possible, think what you do with your regular account and mimic that.
As for requests, if you're just accepting them you should be safe accepting a couple hundred per day, if you're seding friend requests start with a lot less 30-50 a day max and also close the requests if they don't respond after a few days.