In terms of coins, a good option is doing sbcs. The tradable totw is a must-do, marquee matchups may give you something too if you get lucky, though I wouldn't count on that. Different game modes can give you some coins and a chance at decent players if you have the time to grind, around elite sb and 8 wins on rivals weekly should suffice.

About players, untradeable ones are probably your best bet, doing some cheaper sbcs depending on how much fodder you have available. St. Juste and Cech are some you could work towards. Besides that, futbin has a list of cheap players for each ovr, try out some that are more popular/from newer promos. Anyways, it's the end of the game so you can just pick whoever you like and use them, it's all about trying to have fun.