Something similar to the above could be very achievable. (Two bosmans and about £4m on two signings)
Defence:
I think Tavernier could be an option for the right of the back three. He's quick and athletic and has good distribution. He might be better defensively if he was tasked with staying at the back, rather than getting forward whenever possible. He would also be more than capable of playing in the Candeias position.
We need to bring in at least two new central defenders. I've put Ragnar Sigurdsson and Wilfried Kanon for the purpose of this, but there are plenty more available.
Sigurdsson is a fast, strong, experienced defender (he was MOTM against England at the Euros). He's out of contract this summer and I imagine could be signed on a deal similar to that of Alves (if we are lucky enough to find a team to take him, freeing up his wage).
Kanon would cost around £3m from ADO Den Haag. At 24 years old, he has 29 caps for Ivory Coast, where he partners Eric Bailley at CB. He's also capable of playing LB, making him perfect for the role of left in a back three. He would be a bargain at that sort of price and we would almost certainly make a big profit on him down the line.
Other options could include Andreas Bjelland (free), Georgi Terziev (free), Tosin Adarabioyo (loan).
Midfield:
The two wide players have been excellent for us and are capable of tracking back, as well as getting forward. I'm more than happy with Candeias and Murphy, with Tavernier and John providing cover when needed.
McCrorie's role would be similar to that of Kante at Chelsea. If the opposition are attacking down our right side, get over there to help out Tav. Same goes on the left. McCrorie seems to glide across the pitch, covering the ground effortlessly and he's got plenty of dig about him. CDM is definitely his best position and I think he would excel in this set up.
Ryan Jack could provide cover, while Kamara of Dundee looks like having the tools to be coached into an excellent player in this position too. Mulumbu could be a cheap option to provide further cover.
I've put Arfield in midfield. He would be fantastic for us in the middle of the park. I would have put McArthur too, but can see him staying down south. Docherty and Dorrans would fight it out to play beside him in the other CM position.
Forwards:
Patrick Twumasi is a player we should be looking at. He absolutely tore Celtic to shreds in the second leg of their Champions League qualifier this season, scoring twice. He scored a total of 10 goals in 14 appearances in Europe this season, including 3 against Maccabi Tel Aviv, 2 against Legia Warsaw and 1 against each of Villarreal and Sporting Lisbon (as well as his 2 against Celtic). He was very nearly sold to Caen for just under £1m in January. He would be an absolute steal at that price. I've put him in behind the striker, but he would also be capable of playing up front or on either wing. He'd actually be a very good replacement for Morelos if we were to sell him.
Another player able to play in this position is Khama Billiat. He's attracting quite a lot of attention from sides in Sweden, Belgium etc and was close to signing for Qarabag recently. He's currently on around £2,200 a week, so could be a quality addition to the squad without breaking the bank.
Hungary captain, Balazs Dzsudzsak would be another that could be brilliant in this position. He's also available for free and has bags of ability and experience, as well as being superb from set-pieces.
I'd also sign Cummings for the rumoured £600k, not least because we would easily get 2 or 3 times that back for him down the line.