I live in Orlando. Describing Winter Haven as Central Florida is the right approach. You're on the West side of Disney, so every time I drive through Winter Haven, it's pretty smooth.
I haven't actually been to Winter Haven, so can't let you know about the "dated" look it has, but it's a fairly large town about 30-40min from downtown Orlando depending on the Disney congestion traffic.
Housing wise, I've got to think it's way more affordable than Orlando. Orlando home prices are high and you can find a nice deal on a home, but it'll be a mile from a bad area.
It's definitely a growing area as is the whole Central Florida area. It's dead smack in the middle of Tampa and Orlando. Tampa is about twice the size of Orlando if not bigger. Downtown area of Tampa is massive compared to Downtown Orlando, which is actually kinda small, but very nice.
What kind of business opportunity? Publix is headquartered in Lakeland, FL if I'm not mistaken and that's very close to Winter Haven.