Current Homelab Setup

Hello guys. First of all, I'm sorry if sometimes I speak broken English as it is not my first language. I am a 18 year old from Spain and I am currently studding a middle grade in computing and networking (Grado Medio en Sistemas Microinformáticos y Redes, in case another Spaniard is reading) to hopefully become a sysadmin. I have been building a homelab for the past 2 years approximately and this is my current setup. Bare in mind that I have never had a job and all of this was bought with my allowance.

Current homelab under the desk

In the top right we have a HP 260 G2 mini, running a i5-6200U, 8gb ram and a cheapo 120gb sata ssd. This is my main server as it's low power and runs the most critical services. It runs Windows Server 2019 and hosts though Hyper-V a vm with my openvpn instance for remote access, as well as a Ubuntu Server 22.04 vm for general testing. This is the machine I use to manage all of the rest and remote through RDP from class to mess around when in bored in lessons.

The server to its left its the first server i built. Its running an i5 3rd gen (cant remember the specific model rn) 8gb of ram and 4x1tb hdds. This machine is running truenas core and has those 4 drives in a zfs pool running raidz-5. This are second hand hard drives and this redundancy has already saved my ass once. I don't run this server 24/7 due to the electricity prices in Spain right now and I'm not accessing files enough to justify the cost.

The server at the right consist of an i5-4460, 16gb of ram and another cheapo 120 ssd. I run Windows Server 2019 in it and mainly hosts my test vms and heavier workloads the hp cant handle. I again can't run this 24/7 due to the cost it has.

Below all of this is my tp-link gigabit switch. It ain't fancy that's for sure but i got a great deal on it. I would also show you my router but it's in the living room and its just a isp provided s***box. Maybe looking to test build a opensense router just for fun, as i cant convince my parents to change it permanently. For those interested, I have a gigabit fiber internet connection with the spanish isp Digi. If any other homelaber has Digi you know the pain in the ass it is their stupid CG-NAT system. At least I can say its cheap, 20€ a month for gigabit, so cant really complain.

I am currently looking to setup WOL so i can power all of the machines remotely through the hp, that runs 24/7 because of its low power.

Any feedback or ideas for improvement or really any comments are more than welcome.