I mean- to lower one rail at least on the gantry. To be nearer to the bed. Not on top like its now. I know- more difficult.

My point is that if you don't lower the gantry rails like Jonathan's friend machine, you gain nothing with this gantry design.

Yes, i get- the Z will be enclosed and strong, but long...so bearing blocks will be the weak spot.

Jonathan's design is great but changing this and that can make it weaker and not worth it or opposite, better it.

Obviously you haven't seen 2.2kw and 3kw spindles. There is 1hp difference, which could be quite important at low revolutions where there is not enough power. Also the bearings are bigger if i remember correctly.
A 100€ difference including VFD, which i believe is worth investing into.