Martavius Bryant is not a free agent until 2019. And he will cost more than you think. I definitely see it being more than 60% of Watkins' money.
I like the idea of Graham and believe there is a good chance the Rams pursue him on a short term deal. I think the pairing would be Graham and Everett though.
I suspect that the Rams are looking for a TE because they've seen enough of Higbee to know he's easily replaceable. McVay isn't looking for a TE who has to be accounted for; he wants TE's who are threats. Higbee isn't that.
I also like the idea of Bowman. Swapping him in for Barron would be an upgrade.