a question about accepting offers... Watch
go firm on an offer you are 90% sure to meet given you work hard next year. and don't be discouraged if your choice uni gives you a 'high' offer. if you're really determined to get in, think it through and i'm sure with some sweat and blood you'll meet the grades and won't even have to worry about your insurance.
but to answer your question, your insurance SHOULD logically be either the same or lower than your firm. especially if you're talking about top unis with competitive courses.