Server build options from current hardware

I currently have 3 servers running an a Synology NAS as well as a couple of R-Pi 4’s all doing various bits.

The 3 servers consist of 2 Dell Optiplex 7030’s each with 4-core Haswell CPU, 16GB RAM, 256GB SSD and 1TB HDD and run proxmox. The 3rd is running an 4-core Xeon on an Asrock E3C224DI with 16GB ECC, 64GB and 500GB SSDs and 4x4 WD Reds running Ubuntu, housed in an InWin MS04. This is my ‘proper’ server.
The Dell’s run a few VM’s for haproxy, wordpress, and a couple testing machines. The ‘proper’ server runs Nextcloud, MariaDB for nextcloud and wordpress, and Plex. No VM’s or docker.

The Synology is a DS416Play with 4x6TB Ironwolf drives and also runs plex. It’s used for backups and since DSM7 it’s also now my main photos app.

One of the Pi’s is just for home assistant (likely overkill) and the other runs tvheadend, pi-hole (currently not in use), and an internet monitoring stack (GitHub - geerlingguy/internet-monitoring: Monitor your network and internet speed with Docker &).

Everything except my router and pi-hole pi resides in my loft office and use powerline for internal networking. The router and pi and in the living room on the ground floor. I will be running a cable on the outside of the house soon, however.

Now, on top of all of that I also have 2 Ryzen 2700’s, 2 B450 Aorus M boards, 64GB RAM (2 2x16GB kits), 2x500GB WD Blue SSDs, 2x1TB WD Blue SSDs, 3x4TB WD reds, 2x1TB WD Blue HDDs, 8TB external ready to be shucked, 5960X and X99 Asus ATX motherboard, 2x 4port gigabit nics and various other bits. There are a few cases and power supplies as well. It’s all just a bit bonkers really.

The important bits are what I want to host, and that’s as follows:
Plex (video and music streaming)
Minecraft server
Home assistant
Wordpress (fronted by haproxy) or other websites

There is likely more to be added to that list as time goes on, but that’s as it stands for now.

With all that information I’m looking for suggestions on better ways to run the services and how I can consolidate down the hardware. The Dells and ‘proper’ server were my initial plan here, but with all the extra hardware I think I can do a lot better. I’ve picked everything up pretty cheaply over time so I wouldn’t lose much shifting it all on if that’s the best option to fund a better solution.
I live in the UK so used enterprise gear isn’t as cheap or easy to get hold of as the US.

I’m looking forward to your suggestions!