This is one of those things where fantasy players can disagree. I'm much higher on Kelce than you. Mostly because I value the end of the year much more than the beginning and Kelce won people championships at the end of last year. From week 11 on, he had 100+ yards in every game but one. With Maclin and Charles now gone, I think Kelce becomes the focal point of that offense, and I think he has #1 TE upside again.
Plus, now that Cook is in NE, who knows what Gronks target share is gonna be? Meanwhile, Kelces only threat is for the OL to suck so Andy leaves him back to block more like in 2015. But even then I'm not sure how they could afford to do that. I know everyone here is in love with Tyreek but he's a Gadget receiver suddenly taking over the X-Role. Their other 2 WRs are Wilson and Conley. I don't see anyway around it. They will need to use Kelce as a consistent target which is why I'd take him in the 4th over Gronk in the 2nd.
Also, I think saying Eifert has more upside than Kelce is nuts. Eifert has proven he can catch a lot of Redzone targets one year. Cool. I had him that year. He doesn't get yards so if you don't get that TD, you're coming away upset. Not the case with Kelce.