There's a lot of concern about the invention card order. The areas of concern seem to be:
1. Never seeing the exact five bottom cards in (probably) your lifetime.
2. Tedium of setup.
3. Predictability and/or sameness in card order. How much or how little?
4. Honoring the game makers' intent.
5. Stratifying resources (brick, rope, etc.)
This is what you should do (and I may be the first to suggest this):
1. Separate the gold, silver, copper, bronze.
2. Dole out the 10 gold cards into 2 piles; don't let an invention of the same type (ladder, spring, etc.) fall into the same pile.
3. Choose one of the 2 piles above for the bottom of the deck. How blindly or how openly you choose is up to you and the other players. Then shuffle it. You have your bottom of the deck.
4. Blindly pull 4 bronze, 3 copper, 2 silver. Shuffle. This is the top of the deck.
5. Shuffle EVERYTHING ELSE. This is the middle of the deck. You're done!