It sounds like you have already made your decision. I think that a year of research would definitely improve your application. Some of the questions posed to you are definitely worthwhile.
Where do you want to train?
How competitive are you at the programs you are interested in?
Where will you be happy?
Does it made where as much as if you get into a program?
These are questions only you can answer for yourself. One thing you might think about doing is proceeding with your intern year and applying through the match next year, or contacting programs outside of the match for availability of slots. If things don't work out, then you might still be able to do the year of research and not be any further behind the eight ball.
Even while writing this something has dawned on me. You might want to do some research as to how many CA-1 spots would be available this time next year. If you are not as competitive as you might like, doing an intern year might put you back in the same position next year, and forced to apply for spots that open a year from when you match.
Tough decision for sure. I would be honest with myself about my application, and if you are not in any big hurry the year of research and application improvement may be worth it. Not a very helpful post for sure. Good luck.