Hi Steve.
I agree with your suggestion about those burnishing tools for touchups, and with David regarding the scratch brushes for anything more (although I prefer the smaller diameter brush listed on the same page). BTW, to reiterate and expand on what Dave said - when I use scratch brushes for restorations and deep-cleaning, I wear rubber gloves, glasses, and as often as not, a mask - because those little fiberglass shards are VERY stiff and very sharp and hurt you in many ways. But they work amazingly well for cleaning surface gunk and rust off surfaces. Amazing results can be had,
Deoxit - is a terrific product - on things like band switches, rheostats, stereos, and old rotary TV tuners. I used to drink the stuff as a kid (no, I didn't :-). But on a KEY, in most cases, I'd view it with reservations (uness you are in a highly corrosive environment - like Dave, aboard a ship, perhaps). A fellow on the SKCC site reported it made his key quieter so his XYL could sleep; I'll buy that :-) Deoxit is 95% (per their MSDS) volatile carriers that rapidly evaporate. What's left behind - is a trade secret, but is a corrosion inhibitor of some sort. Obviously works on switches. But it is left behind.
Even if that corrosion inhibitor has no negative properties, I question the need; unless you're operating in a corrosive environment (like aboard a ship). And even then, contacts are so easy to keep corrosion-free by simple maintenance, I still question the need.
As for surface corrosion prevention, on keys, the best bet is "Rub n' Brite" by WR. Smith (W4PAL) which is a formulated wax blend. Bill was arguably the greatest key restoration guy ever, and his book "How to Restore Telegraph Keys" is the textbook on the subject - it has some mindblowing restorations in it. He suggested protecting bare metal surfaces like springs on bugs with a thinned-out lacquer, not oil.
General comments on keys and lubes: As the ex-president of a lubrication company (white lightning bicycle lubricants), I strongly recommend no lubricants of any kind be used on a key. Nothing on a key needs lubrication to function properly (there are no high-pressure or high speed bearing surfaces), and with the small rotational angles, low velocities, and low forces in keys, any reduction in friction is likely to be exceeded by the stiction the lubricant will add. Worse, lubricants generally exhibit electrostatic charges that literally attract dust. But even dust just floating by will stick to even the slightest tackiness or wetness and over time, turn into grinding paste. And lubricants migrate from where they are put both by surface wetting and by evaporation and redeposition on surrounding surfaces. Then, just for fun, over time, the volatile portions evaporate and turn the remainder into an acidic lacquer that can be very difficult to remove, and ruins underlying surfaces. Lubricants also tend to be non-conductive and wreck the electrical path on things like trunnion bearings and contacts.
And those are the things I like about it... :-)