I think if you stray from the stock Ibanez switching scheme you're in a little bit of uncharted territory both as far as how to wire it up, and what it'll sound like. That being said, it definitely makes sense that you'll get mostly bridge pickup if it's that much hotter and you combine both pickups, each wired as series humbuckers. However that doesn't mean it'll sound bad! It will probably sound almost like the bridge pickup is soloed, with a tiny bit of neck mixed in. It could actually be a good tone, it's hard to say and it depends on your specific pickup combo. You'll probably get the same effect on position 4 (1 coil of each pickup) and again it could be good or bad, hard to say.
The nice thing about switching schemes is, you can always try it and see what it sounds like and then change it if you don't. If you buy the Ibanez switch I think you can only really do their exact wiring, but if you get the stew-mac switch you could probably pretty easily figure out how to change position 3 into something else.
It's kind of like a logic puzzle coming up with these wiring/switching schemes. I'm terrible at it so I find what others have done online, but you can also figure them out from scratch or modify existing diagrams with just some brainpower.
