Goetze is not a winger and not a striker. He's a double 8. He's capable of playing as a 10 or also as an 8 with a strong holding midfielder, but he's best in a 4-3-3 with a 6 in front of two double 8's. He can play as a false nine and the fact that he outplayed Alcacer in Alcacer's best position playing out of position should tell you all you need to know about his quality. But he's definitely no type of striker or winger. His game is not about goals or assists as much anymore as it is about making passes to put the team into good spots in the final third, helping advance the ball with smart combinations or making good decisions to retain the ball.
He's not going to come cheap, and he shouldn't have to. That was the whole reason he's not staying at Dortmund. He didn't want to take a pay cut. By my rough calculations, his current salary would make him the joint 6th highest earner at Liverpool. Unless the money in football this summer is non-existent all around Europe and the world, I don't think he's going to be taking any pay cut, if he wants money instead of playing for the best team. If you want him, be prepared to pay between 6-7 million euros in wages. And if he really wants to go for a cash grab, he could probably get more than that at one of these ultra-rich Premier League clubs that overpay for quality players, in China, UAE, Saudi Arabia or MLS.
Fans of other teams won't know this because they don't watch Dortmund regularly, but he was absolutely Dortmund's best player last season, and he did that playing out of position. Favre never had any use for him playing in any of his better positions. It's lost Dortmund points over the years, which is another reason why Favre is a bad manager, but it reflects poorly on Favre, not Goetze. Since December he's been frozen out because Favre said he doesn't fit into the new formation Dortmund has been playing with three at the back.
I think his best fit will be somewhere in Italy or Spain like Inter Milan, Napoli, Sevilla. But he's certainly good enough to play at any club in the world.