I agree with this wholeheartedly. The form of Rooney and the nature of lads we've signed make me think we are quite suited to playing a "false 9" which also seems to suit Koeman's high press game. Rooney fits the role naturally, but also Klaasen could play in there, likewise Sandro could do it and even Sigurdsson. I think that's meant in part, that a proper number 9 will not be deployed every week and subsequently we can be more flexible in the quality and profile we go for. What we really need is a lad who will be happy to be a bit in and out of the team but give us a different option from the bench.
You also have to factor in Gana Gueye to this. A lad who was 27, had experience of the league but hadn't excelled, yet we saw something in him that meant he'd be a top player for us in a different system around better players. I could see a lad like Slimani perhaps doing that. He has decent pedigree abroad, good hold up skills, in his prime and will probably benefit being around better players. We'd also be able to bring him in at a price that isn't exorbitant. It's not the "wow" signing I'd hoped for ah la, Dembele or Dolberg and we can only hope we will look again to those lads in the winter or next summer. However I think he would do a decent job for us as part of squad rotation.
This will sound mad, but I'd seriously consider Fellaini if the price was right. With the lads we have around him I think he'd bring them into the game. Will be massively unpopular but would fit the profile perfectly.