So from a professional machines standpoint on Wire EDM there is a lot of fundamental components you will find on all WEDM machines.
The ones they are missing.
1. High pressure flushing pumps. - They clear the eroded material from the cut, the quicker you get the material out of the cut the faster you can go.
2. Filters. - You are reusing the water, so you need to filter out the eroded material before you recycle it. If you don't not only will it plug up the system, the particulate will mess with your conductivity between the part and the wire and thus your cut speed/efficiency as you cut.
3. De Ionizer System - This combined with the filters helps you maintain the resistance level in the water, otherwise you pretty much have no control of your arc gap as you cut.
4. Tension system - The wire extends when heated by the cut process, So with out some sort of a system to maintain the wire tension during the cut, the wire can bow. I think this is part of the reason why they have the feed wire on the bottom, they are trying to use the spool weight to mitigate it.
5. Water Chiller system - Between the cut process an the pumps, it will only take a little bit for that water to be like bath water. For the accuracy level of this system it shouldn't be a big deal, but that baby is still going to get hot.
6. Wire spool holder - That wire they are using, will come on at the minimum a 8lb spool, and then you need to rewind it on to their little couple 100gram spools. It really wouldn't take much to make a wire feed system, as it is basically just a motor that feeds when a swing arm hits a limit switch creating a slack loop that the machine them uses out of.