Hmmm, BUK, you need approximately the number of ticks specified or the precise number? You said "Here, by inspection, we can conclude that the 'best' tick marks would probably be 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09. But that's only 8 ticks..." Is 8 ticks alright or do you need exactly 10? I was thinking about that and it's actually possible to produce 0.02, 0.03 .. 0.09 (and other "pretty" numbers like that), but I find your requirements not very clear, to be honest.