Your cheapest plan offers 512MB of RAM for 5 Euros a month. There's well over 5 competitors who can get you quadruple that amount of RAM and maybe even double the storage for half that price per month. This is due to renting out space at datacenters, no? I'm no hosting expert.
I was in the same boat as you, I'm the type of person that wants new hardware but the keyboard design of the rMBP 15 and the touchbar ruined it for me.
It took some effort but I have a maxed out 9560 running High Sierra, it is very possible and there are a few generous people who have uploaded their config files to github to make it easier for the rest of us.