I would definately give up staff travel perks in order to get paid similiar to BA.
BA crew are paid approx £10k more than Virgin crew. The basic pay is about the same but BA crew also get paid for long range flights, overtime etc. Virgin get paid either nothing or a very small amount £10 for example if a flight is delayed over a certain amount of time. Meal allowances are also much better than at Virgin. All these add up to the £10k extra I mentioned.
Staff travel at VS is good. We get 7 free flights a year + tax. After 3 years these are upgradeable. A very nice perk but don't forget they are on a standby basis so you can't often get on flights. Because our pay is so poor its also difficult to pay for hotels etc when you are away on holidays.
BA (and most airlines) get 90% discount on flights + tax, again on standby. So for example a flight LHR-JFK with VS would cost crew about £80 in tax. BA crew would pay about £150 including tax.
So yes I would be more than happy to give up my staff travel benefits in order to get paid £10k more.
Don't forget that staff travel doesn't cost airlines that much anyway because as staff you only get on if the seat hasn't been sold.