I think that makes your decision. If a healthy Watson rolls out, you go with him. If not, Gordon falls into that spot. I just think Watson has more potential to win games for you by himself. I do not think Gordon has the same appeal. Good luck!
To give you the best answer, you will have to explain your point structure more in depth and keeper rules. Do you give up the round you drafted the player or does your draft start out fresh with every team having a keeper.
At first glance I say Watson because of your statement that QBs are very valuable.
Gordon should have a good year, but there are more question marks with the Browns than there is with the Texans, IMO.
Another question I ask myself is this:
Who would be easier to get in the draft? Then keep the more valuable player and get the next player at their respective ADP, hopefully?