First of all, don't listen to any of us.
Now that is clear I'd first put together a list of goals and budget.
1. You say a semipro look. As in the housing has to look semi-pro or the image? Do you intend to go "professional" and in what sense of the word? Broadcast? Dive shop? Do you just want images you can sell (which would encompass anything from cellphones to 35mm film if the clip is rare enough)?
2. The good cameras allow manual control for all aspects as Mike V said, but the better cameras give you extra control like knee, gain and blacks etc. Sure a lot can be done in post but again that depends if you are going into video as deeply as to worry about that.
3. You'll find that as you grow, your demands for features also grows. But that takes time and usually by then the product cycle is at an end.
So to end, instead of asking for broad recommendations, if you first decide your goals and budget, it would be easier to then recommend a system that fits those criteria. Otherwise you get muddled with low to high end options which is makes your decision making a lot more difficult.
1. The quality of video is what I want to look semipro.
2. My goal is to broadcast my work on a local station and would like to also sell footage.
3. Budget ranges from $2000 - $3000 US
I saw some footage Wagsy shot with his A1 that looked good.
However, if the HC-7 delivers a better quality, then I make could use the carmera; which is in the budget.
My next question is, how does the housing impact
Remeber, Dive Safe