In my opinion, with access to EPL finances and big-money investment, Rangers would be challenging, quickly, at the top end of the table.
Everything at the club (history, mindset, ambition, commitment to excellence/quality in all aspects of the club, work ethic) is geared to make a challenge like that happen.
Rangers are hamstrung by the Scottish environment. It is my dream one day that the club can compete in a stronger league -- my preference being progression through the English divisions. For the time being though, I feel the club should focus on becoming the dominant force in Scotland once again.