No breed recommendations - it's such a personal thing - and if I am teaching granny to suck eggs, apologies - but please don't breed on the assumption that you will be able to sell weaners. Work on selling quality pork at a realistic price and have your market sorted before you start.
Seems all to often folk get put off breeding pigs because they get left with weaners, growing bigger and bigger, and eating more and more - then they get sent to the market, sold for a song and huge loss sustained. End of pig breeding venture.
There seems to be more value added if you sell sausages and bacon than pork but if you get a butcher to make them, any profit will be swallowed up.
Again, I'm no expert but I see a lot of posts on here that make me think pig breeding is hard to make profitable or even break even, given the cost of feed.