honestly - a solid corexy doesn't notice the extra weight of even a hefty extruder like the bond-tech - pretty sure that's what mine uses.
A 40mm smooth iris box printed at 150mm/s - with the slowest being 80% of that and the majority actually running at the full 150 - pretty much answers that question.
You're going to be using proper linear rails arne't you ?

The capricorn tubing sounds interesting - might look at that for my bigger delta.
It's too small for a suspended extruder, but is currently using pretty wide bore tubing.

So what's the capricorn tubing made of ?
Some kind of self lubricating nylon ?

The bed moves up and down :-)

And have alook at this for a PEEK printer !
https://www.e-ci.com/baam