MiniDV vs. HDD
I have commented on a handful of other posts regarding this very issue during the past year and I stand by my long-held opinion: MiniDV is a better camcorder solution than hard drive.
In your original post I find your work flow to be very similar to my own and while the transferring of MiniDV to computer is time consuming it is, in my opinion, the only drawback to MiniDV. And while my post will venture into a slightly different area I would like to address on item you bring up: image quality. Is there enough of a difference due to compression to be of concern? I would say this is a much more important issue now than it was just five years ago. With the proliferation of large screen t.v.'s I believe image quality is more important than ever. Compression artifacts will only be more obvious as screen size increases.
While I have long been a proponent (and owner) of MiniDV over the other available options (until recently: mini-DVD and hard-drive)I would strongly urge you to consider the flash-based camcorder option.
While my Sony MiniDV camcorder works just fine, I am seriously looking at purchasing an entry level flash based device for standard definition recording. I may, however, move up to high definition if I can justify the additional cost. Regardless, I genuinely believe that flash-based camcorders are the wave of the future and in this instance I also believe they make for a far better product than either hard drive or mini-DVD based camcorders.
Unfortunately I haven't yet had the opportunity to fully research flash based camcorders so I cannot speak to the issue of compression, but I believe we can look to issues such as price, weight (and possibly size) and reliability as being favorable for flash based camcorders. My only caveat regarding flash-based units would be to avoid those camcorders with a built-in media card. We all know that flash cards can fail (although they tend to be incredibly reliable) and it is much easier to simply throw away (or send in for replacement depending upon the warranty situation) a flash card that you plug in versus one that is built-in, thus facilitating the need to send the unit in for repair.
Regardless, I wish you success in finding a camcorder that best suits your needs and expectations.