Yes, exactly, just turn DOWN the captcha, don't eliminate it. I have my directory up to about 1300 entries in 10 days. I have my captcha set to numbers only, 4 digits and very little distortion. This works well to prevent spam, but makes it easy for webmasters to submit their sites. When you turn down your captcha, your directory will grow faster.
No doubts man, I submitted a couple of my sites to well over 500 directories. I remember, whenever I used to see a directory with only 4 or 5 letter captcha, it used to be a moment of relief lol. I just can't imagine wasting my time on 8 letter/number captcha. Someone did mention that it becomes a sick game guessing numbers/letters in the captcha when intensity of distortion is too high.
Some are rather difficult to decode, I hear you there. Hell the ones in use here at DP are insanely impossible to read at times. Trouble is the bots that are submitting are now pretty good at deciphering the captcha's. I agree though, the easier to read the better. I've got some of the most clearly easy to read captcha's in the directory industry and I've yet to have any spam as a result.