For me...
Koeman and Walsh need to focus on keeper and defence...it needs alot of improvement.
Centre midfield looks good if we keep McCarthy, if not we need another Davies.
Interestingly, in the attacking midfield, Barkley, Lookman and DCL all have time on their side but we could add one more in there + need someone to push lukaku.
Still a lot of work to be done even if current results are great
Keeper is deffo going to be sorted, one way or the other. Has to be said though that Joel is playing very well.
Central defence is also a priority area. We're dead keen on Keane. I think we may move for VVD come summer, but I'm not sure we'll have much luck...
Central midfield could lose one of McCarthy and Besic mate, and still be full of quality due to the emergence of Davies. I'd rather they all stay though...
Definitely looking for a 'second striker' type as well. Someone who can function in any role across the front line, including out wide if needed.
The three priorities in my book are.
CB - for the first team.
GK - for the first team (Joel may decide on this like, but do think we'll get a 'big' name in).
Striker/Winger combo - for the first team and as an alternative to Rom. Think Mane-type player IMO.
That's presuming all of the key first XI players stay come summer.
Then, two more additions which would be very welcome are of course a back-up left-back (suppose this could depend on Galloway's progress come summer, though I do think it's an are we'll target) and a playmaker***
Jags and Lennon will almost certainly be moved on, as will anybody currently out on loan that isn't a youngster. Deulofeu is up in the air. If he impresses in pre-season, he may have a chance.
***If Del impresses, he may stay. Kev could be moved on if this is the case or even if Del leaves as well tbh. If both them and Lennon did go we'd look to add a playmaker/winger.