History shows that players 'on the wrong side of 30' are almost essential to premiership success. I checked every year back to 2010 and the only premiers that didn't have a single 30 year old were last year's Panthers, meaning they are not the blueprint, they are the outlier. In fact the only other premiership team since 2010 without multiple players 'on the wrong side of 30' were the 2014 Bunnies, who only had one (36 year old Tuqiri).
I know you love big fat forwards and fast backs but rugby league is also a game where decisions need to be made under pressure. The players who are the best at this are the ones who've had the most practice.