The problem: My front cantilever brake has no cable adjuster. As the brake pads wear, I occasionally readjust the cable to keep the pads the same distance from the rim and to stop my levers from bottoming out. However, this means that the cable gets damaged since I am progressively clamping it further up the cable. When it comes time to replace the pads, I'll also need a new brake cable, because otherwise I will clamping at the end of the squat portion.

The specific questions: (1) Am I doing something wrong?
(2) The front cable hanger (like so: http://tinyurl.com/35brdxm) has no adjuster. What sort of adjuster should/can I use? The Jagwire site doesn't help and hardly distinguishes brake cable adjusters from shift cable adjusters. I would like something which can go on the end of the current housing and plunk into the front cable hanger instead of just buying a whole new Tektro hanger with the adjuster already in it, or having to cut the housing and put an in-line adjuster somewhere along its length. (I can do that, but would just as soon rather not).
(3) When brake cables get squat from being clamped, and then are clamped further down their length (i.e. so that the previously clamped-portion is still under tension), does that affect their performance/safety?
(4) Is there any difference between 1.5mm and 1.6mm brake cables? Both in terms of functional difference and actual difference (maybe it's just a measurement variation?)

The details: Tektro Oryx with z-link wire, bog-standard v-brake pads (will replace them with cartridge holders when the time comes, but that won't fix the problem of course), Tektro (or equivalent) front cable hanger, Jagwire housing (no fancy/weird Nokon stuff), Tiagra STI.

Minor indulgence: Is the problem clear? I try to lay out my questions on BF as clearly as possible since I read so many OPs which are a mess.