I'm not sure than any of these four are 'must-haves'. None of them are elite, although Gesicki is the closest to this, and might get there this year.
It took Baker until his third year to have an above average season. 7 sacks from the weak side isn't bad, but this is scheme stuff... nothing he did by over-matching anyone. No interceptions... not real burly in run-support. He isn't just a guy, but he isn't much better than that.
Ogbah, a fifth year player, started fast, and then disappeared as teams realized he was our only real pass rusher. To me, this means that he is a second rank guy who might ask for stat money. Not appealing, if he wants to be paid. His tackle numbers are low as well... To me, this guy looks like a situational pass rusher, more than a starter.
Fuller has lots of talent, but he's another guy who has already played 5 seasons and likely has a probable low upside. Plus, he's never played more than 14 games in a season. He's less durable than Parker. I damned sure wouldn't give this guy a long term contract... 2 years max.
Now Gesicki... He's missed one game in three years and has gotten better in each year. Like almost all tight ends, his first year was forgettable, especially since Adam Gase was playing him incorrectly. Gesicki is a slot-style tight end... you know, the modern kind... like Sharpe and Gonzo... and Gates. He put up career highs in yardage and TDs last year and did this despite playing in a constipated offense with no speed or deep threats to keep him from being double and triple covered. Quite honestly, I expect him to push 1000 yards and 6-10 TDs this year if he remains healthy-- which he always has.
Gesicki is the guy to lock up. Long's arrival does nothing to diminish what Gesicki brings to the team. Long is a Y-style tight end and the two of them could easily be the best set of Tight Ends since Gronkowski and Hernandez. If I'm faced with the choice between 4 years of Fuller at 18M/season or 4 years of Gesicki at 13M/season... I sign Gesicki so fast that your head will spin.