1) It's impossible to give too much love, but it is very possible to adjust PH too often. Plants really don't like that. Adjust PH to 5.3 to 5.8 (I prefere 5.5) and leave it there. Your PH will most likely go up over time and this is OK as long it doesn't go above 6.

2) It's impossible to have your light too close and too strong unless it is stressing the plants. VERY SLOWLY keep decreasing the distance between the light and the plants, while keeping close watch. As soon as you notice a little light stress, back off just a touch, and keep it that distance from the plants as they grow.

3) I don't think paper towels in the roots will do any harm. But I use a cheapo cloner and have a bigger root mass before putting them in the hydroton.

I disagree with stinky. I use nothing but hydroton from start to finish. If your youngsters aren't getting enough water, just increase the cycle until they are a little older. I water about every 10 minutes or so, for about 30 seconds.