For example, we have been linked with Lacazette, who would cost at least £50mil. Now, I am thinking, is he that better than Martial??? He might be more experienced, but I wouldn't be so sure that he is better, especially as Martial has more space/time for progress.
For me Lacazette, Morata, Lukaku, Kane seem all like good youngish strikers. But they're just that. Good and young. Are they exceptional? I'm not so sure. The one who stands out is Mbappe. That's the level we should aim for. I don't know enough about Lacazette and Morata to be sure that they're not exceptional, but I guess we'd have a lot of noise about them being special if they were that great.
That's the problem for me with signing someone like Mata as well - he is good but he isn't exceptional. It shows ambition if you buy someone like him. Just like it was with Fellaini as well. He is a good player by regular standards, but he is not one of the greats. All our transfers should be viewed so that the player we sign either is or could be exceptional in some way. It doesn't have to be that they all have exceptional skills, but some might have exceptional work ethic(like Park), some might understand the game well in many positions(like P Nev or even O'Shea) or someone might have more of a moral boost to the team(I think Zlatan this season was like that, it felt that the young players looked up to him a lot, Cantona was obviously another).
If we're happy to sign someone who you can clearly see isn't special, then we're going to end up as just another good team.
Signing attacking players is tough. But for me the strategy has to be clear - either buy players in the 22-26(but more 22-25) age range who are already at the top or younger than 22 who have the potential to be at the top level. Buying older players comes into question only in exceptional cases(Zlatan being one of those).
For me with those young strikers there are questions - is Lukaku good in a top team? Playing for Everton is different to playing for United. I have some doubts.
Is Lacazette going to do as well at a higher level? He is supposed to be a readymade player already. Someone like Martial or Mbappe has more time to adjust.
Morata looks like the best option for me, because he has shown he can do it in two leagues and for dominating teams, so that means he isn't a counter-attack striker like Lukaku is IMO.
Kane is very good, but he won't leave Spurs.
As for wingers - I think there are very few wide players I'd be really excited about. The 'good' level of Mata, Miki, Martial and Lingard is the level to beat. That isn't so easy. Memphis in Ligue 1 tore teams apart but couldn't get regular games at United. For me there is a short list of wide players I'd really like to see at United:
Neymar, Ousmane Dembele, Bale, Ronaldo, Messi, perhaps Lemar, perhaps Lucas Moura(still 24!), perhaps Mahrez, perhaps Pulisic. But others are probably not going to improve us enough to be worth the inevitable 30m+. That's the level we should be aiming for. Hazard and Sanchez would improve us as well but I feel the price will be too high and they're not worth it because of that. Liverpool(Coutinho) and City(Sane, Sterling, Jesus) have young wide players who would improve us as well, but that's out of the question IMO.
As a backup striker someone like Chicharito would be perfect I agree. If he is happy not to play every week.
I just hope we don't sign Diego Costa. He seems available now as he just said today that Conte doesn't want him at Chelsea. Although it would be funny to see a strike-duo of Fellaini-Costa. Throwing elbows at their opponents. The officials couldn't keep up :).