Your list isn't a bad start. Is audio important to you? I would look into some kind of external audio recorder.
The LCD on these cameras is very good, but attaining focus is definitely more challenging when working with them. Some don't need it, but I would still recommend a viewfinder (especially when shooting outdoors during the day). There's a bunch of different ones out there, but I've mostly used the Zacuto Z-finder and the LCDVF viewfinder. The build of the Zacuto's stuff is top notch and it works really well, but I honestly prefer the LCDVF. My eyes don't require a diopter and the price can't be beat.
Yes, there is a 12 minute recording limit and it has to do with how the file system works on these cameras. They can only record files up to 4gb large (which is usually the 12 minute mark). Other cameras technically have the same limit, but their internal software automatically creates a new clip at the limit and keeps recording. Canon hasn't implemented anything like this on their cameras yet.
Another drawback to these cameras is the overheating. This has to do with environment and how hard you work the camera. Conceivably you could continually record a bunch of 12 minute clips in a row, but chances are the camera will start running hot and want to cool itself down, so it shuts down temporarily. This is manageable when doing stuff that's controlled and planned out, but could be troublesome on live shoots or any other situation where you can't re-shoot should the camera overheat.
The lenses you list aren't bad, but you really do get what you pay for when it comes to it. The zoom you list has a variable aperture. That means that it won't maintain the same aperture setting throughout the whole zoom range. Were you to shoot something say at 100mm 4.0 then try to zoom to 200mm, it would stop down to 5.6 and change your exposure. You can work around that, but could be an issue during a continuous shot.
If you want to get into prime lenses, there is a great market out there for affordable used ones. Check out ebay. And don't feel like you need to be chained to the Canon lenses. You can get an affordable adapter and use almost any type of lens mount you want.
IS is a godsend for zooms, but be aware that the IS mechanism makes some substantial noise that will be picked up by the onboard audio should you not have an external recorder.
Check out the following link for some great recommendations for all budget levels:
http://www.dvxuser.com/V6/showthread.php?201716-List-of-great-EOS-lenses
One thing I forgot to mention is that you'll also probably want a variable ND filter or set. There's no use in getting a fast lens and opening it wide up only to find that you're tremendously overexposed. Other filters are nice to have, but are really just extra. ND is a necessity. You might also want to get a cheap UV filter to protect the front of your lens.
I am in no way trying to discourage you from making the jump to DSLR, but just wanted to pass along some of the info that often gets ignored. No one can tell you if you're making the right decision or not. It will certainly be a challenge, but it's for you to decide if you're up for it. As seen, the results can be breathtaking, but it takes some work.
Ultimately the best thing to do would be to see if any local shop rents these cameras. Take one out for a test drive and get a feel for it first.
