There are regular tourist trips to go on, and they can be fine for photographers. The advantage of the trips that are oriented toward photography, such as the ones that I do, is that we control to some extent where the ship is and when, so that we can be at the best places for the best light. On regular cruise ships people want to sleep late, be back for afternoon tea, and such.
As for being on a beach with 40+ other photographers, that's an image based on misconception. Yes, you get off the zodiacs at one point, but then there are vast areas to explore. Other than the sensible safety rule of always being with at least one other person, which (can be fun), it is possible to completely avoid being with anyone else for long stretches of time while shooting.
And on the zodiac cruises (one of the best times for shooting) on a regular trip you'd be fighting with tourists who don't understand the needs of photographers. On my trips everyone understands how to get low on the shooting side so that others behind you can work. Also, the zodiac drivers are told how to position the boats, something that doesn't happen on a regular trip.
Finally, a trip like the ones that I organize have several photographic instructors onboard who provide lectures, print review sessions, etc, on a daily basis. These are people whose courses normally cost hundreds of dollars a day, IF they happen to come to your city.
As for crossing the Drake passage, there's no way to avoid it. It lies between South America and Antarctica and takes some 36 hours to cross. I simply regard it as the cost of admission. I've now crossed the Drake 4 times, each time I was in my bunk for most of the crossing. Not actually sick, but happier to be lying down that standing up. Some people are unaffected.
I haven't finalized the details yet, but I am talking with Quark about chartering one of their ships for January '09. This would be an extended Antarctic penninsula trip lasting about 13 days. I hope to have more details in a couple of months. It will also likely be the last Antarctic trip that I do.
Anyone wanting to be on the waitlist should drop me a line