There is no real need to lower anything ... If the mice cant reach it they will jump up and hang from the mesh ... doesnt create any problems at all. The more divisions, steps, ledges, etc. that you have increases the liklihood of an escapee. So I tend to keep everything as simple as possible.
I actually have the automatic watering system you are referring to ... Once I had it fully installed I couldnt ever tweak it to where I was really happy with it ... so I replaced it all with water bottles. The choice is really yours ... I prefer water bottles ... but now that I am refilling 100 a day im seriously debating putting the auto waterer back up.
My mice watering bottles are 250 ml. 70 cc's = 70 ml ... so that shouldnt be a problem ... but it will require daily attention. The max 70 ml will last one of my setups of 1:5 is 1.5 days (they go through about 50-75 ml of water a day)
Bryan