What seems to stand out for me is lack of planning to have so many contracts expiring simultaneously.
It has the distinct look of a disaster waiting to happen.

There seem to be many players we'd like to lose but will have to offer new contracts to.

I hope that it's an opportunity to blood some youngsters into the squad (some hope).

I think it'll need some careful and inspired management to come out the other side with a decent squad.

I have now sufficient funds to last me the rest of my life. Provided I don't buy anything.

Because of the way we are setting up with a low block when we get the ball the players are too close to each other and there is little opportunity to stretch the opposition. This means we either look for a quick break with one or two players carrying the ball 50+-yards upfield, we hit it long in hope, or we end up passing sideways and backwards until the opposition has had plenty of time to recover and get men behind the ball. The opposition also know that they can simply foul Eze, Andros or Ayew inside our own half to limit any threat on the counter. It might be crude, but it seems highly effective and something we often have no answer to.

If we had a big man up top who could make the ball stick this could help us get out, but we do have a severe lack of pace meaning there is often a huge gap between the forward(s) and the midfield (again due to the low block). There also seems to be a distinct lack of movement when we are in possession meaning our more creative players often end up going backwards due to a lack of options. This is one of the most significant things that goes missing when Wilf is out, as he goes looking for the ball and looks for the best ways to link things up.

It's difficult as when we were a bit more expansive for a few games we conceded a lot of goals and looked so open. Probably the most important area we need to look at for next season is adding pace through the middle both in defence and midfield as until we do that we will struggle to play higher up the pitch without being exposed.

This is 100% how I see it.
We are very easy to stop as set up currently.
I’m amused by commentators who talk of our counter attacking strength and pace on the break, in particular in the absence of Schlupp and Zaha.
I hope we’ll be seeking to address the lack of pace and energy in the next windows.

or, it is part of the masterplan to overhaul the squad, and there's some bigger picture stuff happening behind the scenes, which will see a cash injection, new manager, and that new manager bringing some signings from his previous club to help bed in the new positive style of football. We can dream right?

That's the frustrating part as it shows we are capable of passing our way through an opposing team. We have some very skilful players in Eze, Jairo, Ayew, and most notably Wilf, while players like PvA and Schlupp are very adept at finding space in behind defences; however, as you say, these brief glimpses are becoming less frequent as time goes by.

Having watched Gallagher a few times recently I'm becoming increasingly convinced we should move for him. He looks like a young McArthur, with speed, tenacity and a willingness to work hard at both ends of the pitch. Doesn't really look suited to a top 6 club as he's more of a scrapper, but definitely looks like a player who would fit in with us.

That about sums it up. The only thing I would add is that your last sentence , tells why using a low block has been used so often. We have been exposed to often this year particularly. Not just of late. The Villa, game comes to mind.
It is true the play does become very condensed in a low block, but it is only a partial excuse, the players do need that bit of composure , quality to cope well. In the Brighton game I could not count how many times after much chasing shadows, the ball came freely to one of our mid fielders, and they couldn’t make the first simple pass which was on, let alone take part in something more expansive. When it comes to good offensive football it is so much reliant on movement , but it has to be movement in every direction for every purpose. Only if you have that can you not get exposed.
It’s been said many times here , it does need stirring up, it’s a four or five player job as I see it throughout defence, middle, up front remains to be seen, and might improve if the rest is sorted.