I had a WaveMaster back in '03/'04. It was definitely deficient in the cooling department, and many mods have been proudly displayed by case-modders since then, some even sporting a water-cooling system.
For the most part, the intake air-holes on the case front are insufficient (behind the decorative aluminum "monolith.") Some of that material could be cut away with a dremel without compromising structural integrity, and additiional paneling could also be installed -- frames or duct-boxes -- with pop-rivets. This would be the most tedious and reluctant of mods for this case, since it is certainly a beautiful case and no owner would want to compromise that beauty.
The poster who used an 80mm-to-120mm plastic fan adapter is probably to be commended for choosing the least expensive and simplest rear-case mod. My only reservation about that approach is that the fan protrudes farther than its width, and is only joined to the case with plastic. Obviously you would prefer to simply cut a 120mm fan-hole, and even if there is room to do so, you could mount an aluminum-frame fan like the EverCool on the case exterior. But I don't think there is enough panel "real-estate" on the case-rear to allow for cutting such a hole.
Barring the tedious and potentially aesthetically compromising front-case mod I mentioned, it would be quite easy to install bottom fans in this case, but you would then want to mod the case to lift it up above the floor or carpet to admit air to the bottom intake fan(s). Such would be fairly easy -- I use double-wheeled casters on my case-mods, allowing the case to clear the floor by as much as 2" or 3".
You could also pop-rivet U-channel aluminum lengths -- carefully cut for a good, neat fit -- to reinforce the case-bottom for such fans, and provide a duct-box and filter-tray -- which could also be augmented with a panel of steel or aluminum modder's mesh. Such a box would clear the caster wheels.
Finally, if you choose the caster-wheel route, you can also increase stability and actually augment the appearance of the case by bolting or pop-riveting bars of 1/4"x[2" or 3"]x10" aluminum to the front and rear of the case bottom -- perpendicular to the case sides -- so that the caster wheels extrude an inch or two from the sides of the case.
I'm busy today, don't have time to grab the photos of my Compaq Proliant Server mod for display here, but with the cross-bars and casters, you can round the corners of the casters and then tap holes that clear the caster-mounts so that you can cap the protruding upper sides of the aluminum bars with 1/2"-high pieces of aluminum heatsink material -- which provides a more decorative appearance.
Well, I have time to stick in one photo here, although it shows my workspace and office to be a mess:
My Great ProLiant Server Case-Mod
For the WaveMaster, you'd use 1.5" or 2" double-caster wheels, as opposed to my 3" jobs shown here. And you can see the ribbed caps I mounted on the upper-side of the wheel-mounts.