To be honest cant see any premier team wanting to move up to the EL in its current form. Costs being the main issue, with GP riders running a close second. The teams talked about earlier in this thread would all be affected by the GP's, Workington race on a saturday so would have the same problems that has affected Coventry over the past few years, the BLC has hardly been a major success with cancelled meetings etc. Arena would also be affected as GP practice is on a friday and in some ways Sheffield and Swindon would also have difficulties has riders would want to be on their way to the continent by Thursday afternoon.
With the current issues regarding GP riders not wanting to fullfill their rides or matches in the EL, the only solution to a bigger league is for the GP riders to make a a choice between the EL and GP's.