Is it OK if I can feel fiberglass cloth texture after curing?
Perfectly normal, and unless you have some need for it to be smooth, not a problem. Many less-fancy fiberglass products have the fabric texture exposed. 

The bigger concern for longevity is then covering that material (which is highly subject to sun damage) with an adequate layer of paint to protect it from the sun. 

Since you mention that you are preparing for paint, sounds like you'll have that covered.