Thanks for responding. I am using a Seasonic PSU with my hfx classic by floating the PSU.
This is not optimal and the usage of one 'bay' is lost.
Am planning to do a jbod/raid with multiple SSDs (as 1-2tb are expensive now), and while 4 can fit into a single 5 inch bay, I think the additional cabling would also make a mess of things as things are really quite tight in there. The gf is complaining my only remaining standard harddisk is noisy in the room.

As an alternative I guess I can consider PCIe SSDs...
Ideally I just want something similar, but much taller so I have more space on cable routing and future expansion.
As a side note, I primarily use this system for audio purposes and it's quite audible when the PSU is placed in a more stable position + cables are routed neater, so this is just a preference. I'd not mind something like the Level 10 system's size but unfortunately don't think its possible to do passive cooling on that. I guess something like the old Zalman TNN500 (though I've not seen the internals) might have been ok...