well I took econs SL so I'm obviously biased here and will tell you to go for econs. I found it really easy. however, seems like you'll be taking econs at HL if you do choose it? I think econs is much more theoretical so if you like theory it's for you. even at HL, I still feel that the amount to commit to memory is less than what you have to for business HL. it's mostly just understanding certain economic models, diagrams, and such. don't have to worry about the math part since there's no math in IB econs at all. however, if I'm not wrong, there seems to be a lil bit of math in business. shouldn't be anything full blown though.
you also said you didn't like to apply theory. well both subjects are more or less on par here, econs has 4 IAs which require you to write a 650-750 analysis on a newspaper article demonstrating real world application of economic theory. business has a single IA which, in my opinion, is a lot more work then the econs articles. you need to find a real world company and gather their data and such. possible questions include whether they should venture into new markets etc. as you can see, quite some bit of application of theory as well.