Personally I believe any bachelor tax should really only be a bachelorette tax. Childless women should be taxed but not childless men. The reason marriages are not occurring is because women on average don't want to get married young. If women wanted to get married between the age of 18 - 25 they would have no shortage of men wanting to marry them. So the problem is largely caused by females hence they should pay the tax.
Tax rates are not going to change their behavior. They should instead have companies discriminate against hiring young single women, in favor of married mothers with teenage children who want to get back into the workforce.