I totally get the reasons why you trade Bello over Crawford and hold onto KC in hopes he rebounds from a pretty small sample size of struggles.
I value Bello way more than Sandoval/Crawford/Harrison. I'm not looking to get worse at one position or slot, but as with any trade, if we gain by much more at another slot, I'm all ears.
The drop off from Bello to those three is much more than the drop off from Sandoval to Crawford, IMO.
The drop off from Masa/Romy/Campbell at DH is much less that the gain we get by trading Duran the DH for a thumper 3Bman/2Bman. That's how I view trades and who to choose. It might be oversimplification, but I think my philosophy has merit. The drop off from trading Rafaela and playing Anthony or Duran in CF is not much either. I'm open to trading him or Abreu to, despite both being among my favorite players.
I know some feel Bello is not as good as his ERA shows he is, and this is a trade high moment. That view makes some sense. His $9.2M AAV is also a reason to look at him (or Sandoval) as a trade chip. I will say that those salaries also exclude many teams from even calling and will lessen the return that maybe a Crawford or Harrison might bring back. (Not equally, but in terms of value per salary)