The US is stuck in the past

I'm not saying that tradition is a bad thing, or that ties to one's past isn't beneficial. Remembering the mistakes and triumphs of our past help us function better in the present and plan for the future.
But after a visit to Springfield today, after seeing how much money the capital has spent re-doing the building to look like the original capital, hiring east-coast artists that can mold plaster, and spending huge amounts of money on expensive materials that serve absolutely no purpose, I realize that we are stuck in the past. Huge amounts of money that could have gone to education or health care, are put into the hand-moulded plaster and imported crystal and granite in our state's capital building that almost no one ever sees, and instead of spending that money on what this state really needs, our government put it into trying to recreate the old capital building. Having a modern building wouldn't hurt anyone, and might even bring some pride to our capital, that at least part of our government is moving with the times.
This reminds me of our constitution. We have the oldest constitution of any democratic country in the world. I'm not saying that this in itself is bad. My concern is that if that document no longer works, or slows down the government process, or leaves out important ideas necessary to the protection of citizen's rights, the need for a new document should outweigh the pride in having the oldest peice of paper to base our government on.
I'm also not saying we're there yet, just that this is an issue that needs to be considered. How much are willing to give up for our pride in having the longest-lasting constitution?