Any comparison between British and Spanish colonial experiences is going to be flawed because there were so many variables occurring during hundreds of years of interactions, socioeconomic developments, unique challenges to particular geographic areas, and changes in governance, economic systems, military strategies, and culture. I've been meaning to put J.H. Elliott's Empires of the Atlantic World: Britain and Spain in America on the AH booklist for a while now. It is well researched and written and has tons of end notes. I think it is about as fair as a comparative history can be in this context. Elliott relies a lot on other scholars' work, so once you've finished it, you will want to dig into those sources and others on the AH's book list. The book does not really get into why there are economic disparities between the North America and Latin America today, but that question really cannot be answered fairly by singling out their colonial experience or differing dominant religions without getting into some really sticky "black legend/white legend" debates or problematic definitions of subjective terms like "advanced" or "successful".

You might also want to explore some Atlantic history. I learned a lot by reading Atlantic History: A Critical Appraisal, which has descriptions of several imperial systems in the Atlantic. There are also a number of Atlantic history flaired users whom you could contact for more recommendations. Maybe they'll even comment here too!