Definitely Not An Old Poster
15 - 20 goal contributions would be incredible for a first season but that might be setting your expectations a bit high. That would be on par or better than Grealish last season for example. 12-14 league G+A this season and he's done well in my book.I think 30-34 million is a good transfer fee. As long as he doesn't turn out to be completely and utterly useless and/or permanently injured we should make out alright regardless. This type of fee also means he doesn't come with that big baggage of needing to turn it on and be top, top class every game like he would if he was a +50million signing.
If he plays 30-40 games this season and chips in with ~15-20 goal contributions I'd be happy with that.