It's based on the ZoneMaster II. It would be fairly straightforward to put keyholes in the base so it could be hung on screwheads.
I like it that the timer is small, and probably light like the paper flasher. However, that means it will move easily when moving the cord around, fall into things, etc. So I would like some built in ways of securing it short of screwing it into the wall. I guess I could tape it or use blue tack but something more elegant would be nice.
Glow-in-the-dark tabs are available and much easier than adding an LED and the necessary extra battery. Heavier footswitches are available but they tend to be for industrial purposes and are very expensive. If it tends to slide about, try some self-adhesive Velcro pads or a big blob of Blu-Tack to stick it down. Extension cords are available. Believe me, for everyone who wants a longer cord, there'll be another who thinks it's already too long and gets in the way :).
For the footswitch, a long cord option would be nice. If I mount it on the wall and have to snake the footswitch behind the sink, etc. I would need a 3-4 meter cord. Also, I think that the footswitch for the timer is too light. It does not stay put and just the tension from the cord forces it out of position. Some type of weight in the bottom would make it more stable. A cool option would be to put a very dim, optional LED safelight in the footswitch so that it is easy to see in the dark.