It will depend totally on you. Since I am used to steel strings and a certain amount of string tension, I preferred to use hard or extra-hard tension on my nylon Taylor 314-N when I had it, for a similar playing feel. Otherwise I had to struggle at lightening up my touch compared to my other guitars (I have very strong hands). There were no ill effects on the guitar.
The variation in total tension ranges from 90 - 115 pounds, give or take, for different sets of nylon strings. Light gauge steel strings start at ~160 pounds, with mediums at ~185 pounds, and a twelve string light-gauge set at 250 pounds. You might need to make a minor truss rod adjustment to subtly relax the relief when using much lighter nylon strings. Hope this helps.