If your kids have never been to the parks before, they won't know what they are missing. Plus, as someone pointed out - something is always closed during the off season. Crowds are smaller, so the experience would be more enjoyable. DL is our favorite park. We were there Aug 2010, and could have spent all 4 and a half days at DL alone. There were parts of the park that I never got to, partly because we did go to DCA.
Plus, your kids may have their own ideas of what they want to do. DD (6) had her favorite rides that she wanted to go on over and over (and over, and over ...). She did not care that she went on ALL the rides, she had her favorites and she stuck to them. Like Gadget go-coaster 11 times ... (!). I did not bother counting her trips on the carousels, I knew it was going to be a lot. There were several rides she was not interested in that I persuaded her to at least try, but she did not enjoy it (didn't feel the magic) so that was wasted time. Even when she went for the first time (at 2 and a half) she knew what she wanted to do.
So, I would not hesitate to go, even if you decide to avoid DCA or deal with the construction, then let them decide what they want to do. Have fun!