Removing veins impairs blood flow to that area, but since the varicose veins aren't really getting blood efficiently to their locality anyway, I wouldn't call the lack of perfusion from removing them a drawback, per se.
Some complications can arise following surgery to remove varicose veins. Some of them are pretty innocuous, like skin discoloration, but ...
Veins pop out when the muscles are strained.
Muscle builders try to get them popping out with constraining the blood flow by tying something to their arms. The compression socks and pantyhose may work in a similar way.
A professional hair removal laser machine doesn't purposely heat up the skin, most machines for hair removal are using a wavelength with a short burst cycle that will heat up the melanin in the hair and use the hair shaft to transfer the heat to damage the hair bulb.
A professional hair removal machine with correct settings shouldn't have any effect on ...