Nope, your observations are basically correct.

However, if you decide you don't want the very basic "come with" servos for your next plane, or you want a different battery pack or whatever, you can go for flexibility and not have a bunch of stuff you aren't going to use. For example, you might want smaller, lighter servos for a small plane, or higher speed and torque and higher percision. Or you might want a larger capacity battery pack. Who knows what you might want in the future.

For me, it's a no brainer. Flying combat, I frequently have a "huge" pile of airplanes ready to go for a contest. (I actually flew 10 different planes last weekend in 3 different classes). I have a Polk transmitter that has a 99 model memory. I also use 270mah batteries to save weight, and micro servos on throttle and differnet servos on other controls depending on the plane. So, for me, a computer radio and tons of flight packs is a no brainer. It's also nice that I only have to charge and keep track of 1 transmitter, and the stick feel is always the same.

But if you are just flying 4-channel sport planes in the .25-.60 size range, then you're right, there really isn't a compelling reason to go with flight packs. You save a little money, but not a ton. I, on the other hand, have save buckets full of cash by shopping around for components.

Also, it's worth mentioning that many of the useful features the computer radios have are not available on the less expensive 4 and 6 channel models. I use a lot of expo on my planes, for example, and that isn't (or wasn't?) available on the lower-line radios. Once you start using mixing and other advanced features, the cost advantages of a flightpack really start to show up.