Some more antenna and gear advice for new Leamington house
Just adding that from Leamington you will of course get Detroit but if you invest in deep fringe gear on a rotor and tower (I'd say a preamped Channel Master 4228 UHF and a preamped Wade-Delhi 307 VHF/FM on a CM9251a Rotor atop a 20 foot tower anchored to your soffit overhang) you will get Toledo OH and Cleveland too, and in the other direction London. TwilightCowboy mentioned Flint MI, too, which I did not know was a possibility too. What a choice of stations!
If you just want Detroit, I'd second Yaamon's CM4221 choice and I would not bother with a rotor but I'd also add a Wade-Delhi 306 VHF/FM to cover remaining VHF channels but also for the FM radio from Windsor/Detroit. Mounted on a tripod or other such roof mount, you'll do great.
About the splitter idea: since you're stringing RG6 throughout you should be fine for strong signal, but still I would recommend that you rough-in a place for a distribution amp on your patch panel (with AC socket for it) just in case. Once you've got things ready for testing you could see if the signal at each end point outlet using the splitter is strong enough. If you find that the signal is too weak you could just swap the splitter for a low noise distribution amp and that should fix things. I would test with the splitter first and not go directly with a distro amp because you don't want to overdrive your system right from the start.