Since this game is made for multiplayer don't really expect SP to be that good. The bots are like gods in the battlefield while your team if full of rookies, you'll have to keep going back to a checkpoint to bring them back while the enemy advance like there's no tomorrow.
if you're on windows 10, it might be your display settings, under personalize, there's an option to magnify all items by scale (it's a slider) if its above 100% , which it's defaulted to 125% iirc, just turn it down to 100%,, logout, and log back in (to your windows account) that should fix the issue
have u tried the game on hamachi? Im not sure how to host a server in the game, maybe in the singleplayer mode, the grit mode is the one who creates the server, but im not sure.
that should fix the issue
My mouse always goes in the bottom right hand corner...
(yes it is still EA, no wonder tho.)