Orchid heavy ExoTerra

[Trollsvans]

ExoTerra 30x30x45 cm (12x12x18") with Epiweb drip wall on back side and one half side, plus a bunch of DIY Epiweb roots and lianas/branches.

Current inhabitants are:
Bulbophyllum fascinator, taiwanense and frostii
Epidendrum porpax
Masdevallia norae x2
Schoenorchis seidenfadenii x2
Platystele misera
Pleurothallis niveoglobula
Various stowaway ferns and (possible) gesneriads from the moss mix (and mosses, of course).
Larry the Giraffe

The setup is rather straightforward: epiweb covered in moss mix, covered in orchids. A mini-fan is running daytime and intermittently nighttime, the waterfall runs for two minutes four times a day.
I'll be adding another mini-fan soon, just because I found a spare at home. I'm thinking along the lines of "one on, one off" and "redundancy in case of breakdown".
Humidity is usually 70-100%.
Lighting is 2x23W compact flourescents in ExoTerras standard topside mounts.

The tank started in late February, and got the M. norae and P. niveoglobula in mid march (or rather, half the Masdie and a third of the Pleuro, the plants were rather big, and the tank very much isn't), so they're more established than the rest, and growing well. The Pleuro has been flowering since just after I put it in, and seems to continue to do so for a while.


Unfortunately, the tank looks rather unbalanced at this time: most of the plants are orchids (while I don't mind this, there are so many other interesting plants to have), and they're mostly located in the lower half of the tank.
Anyone has tips on plants that'd do well in the upper half (say, on the liana "shelf" to the left, for example), I'm mercifully accepting them.
Orchid or muggle plants (non-orchids, that is) doesn't really matter, but blooming or handsome foliage is preferred over plain evergreens.
I'm open to suggestions regarding plants (again, any type) that might like the more shady areas as well, because if there's space, it means I've got too few plants.
I'm hoping for plants that are rather easily aquired, and, considering the tank size, not too fast growing.