I've seen fluid that looked like it should be in a coffee cup - right down to the consistency I like ("coffee by the slice...")
Smell? ATF seems to smell just a bit "odd" (burnt?) when new, so that's fairly relative as well. However, burnt ATF is very distinctive - you'll know it immediately (in much the same manner as you can tell gear oil simply by smelling it, and tell whether it's got LSD Friction Modifier in it, with a little practise...)
ATF does NOT retain that "bright red" colour once it's been run - much like engine oil, which does not retain that fair amber colour after about a week (unless it's in a Diesel - when it turns black just about the first time you start the engine and let it run for five minutes...) However, colour is still a useful indicator - it will remain "red" throughout its useful life, just not obviously so. It will fade from "bright red" through a "medium red," through brown (you haven't changed it yet?) to black (you haven't changed your transmission yet?)
Heat is the main enemy of automatic transmissions - a properly sized cooler does assist greatly in fluid longevity! ATF additive packages, as I recall, start to break down in the 190-200*F range, at which time you start to lose "friction modifiers" (for the wet bath clutches) and "varnish preventers" (so you don't crap up the valve body - think atheriosclerosis, but worse. "Calcification of the brain tissue" is probably better... The valve body is the "brains" of the automatic, and I've seen some that were REALLY ugly! I mean, none of the check balls could even move...)
Light to medium brown fluid is something I'd keep an eye on with the AW4 - you've already changed it, so watch for any changes in operation and performance. One sign that fluid has run ENTIRELY too long is that the fresh fluid doesn't do anything about clutch slippage (because the bronze friction discs and steels are now coated with varnish...) and the condition persists after, say, three weeks or so of daily operation after the fluid change. If the fluid has gone for a while, a little slip is normal after a change (if you were slipping before,) but it should clear itself up.
Dumb question - I don't suppose you have a decent picture showing the colour of the fluid, do you? My definition of "coffee" is likely different from yours (in my case, I'm thinking "oil black." Most people define "coffee" as a sort of "coffee with cream" colour. A good picture should eliminate confusion.)
Helpful hint - if you aren't sure of the fluid colour, have a bit of white plastic handy. Dip it in the fluid (don't mix it with anything else!) and use that for a comparison board. Check the fluid with the plastic still in (gives you a "graded" colour in bulk,) and then withdraw the plastic and check for a change in colour IMMEDIATELY (which will tell you just how contaminated the fluid is, with a little practise.) Take pix the same way, if you want a second opinion.
In a pinch, a Popsicle stick or a tongue depressor painted gloss white will work, but you should have no trouble finding white Styrene at a hobby shop or a hardware store.
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