A slow centre back is also a disadvantage. Right now, we have Maguire who is one of the best in the air, but he is also very slow on the turn, albeit with a decent top speed. Then we have Lindelöf who is not good in the air and is also slow. Bailly is plenty quick, but he is very erratic in the air. I think both of them are at least to Gomez' quality in the air and about equal to Stones. If you have one really dominant aerial defender, you don't necessarily need another if they make up for it with other attributes. Giroud, Jimenez, Calvert Lewin and Kane are players Maguire can handle. Kounde should definitely be able to handle players like Antonio, Vardy and also Calvert Lewin and Jimenez. Perhaps more pressing is how many goals we concede from corners etc, where one of the biggest concerns is DDG and his reluctance to come off his line.
Would you really categorize Gomez as formidable in the air?
Edit: Ramos is only 6cm taller than Kounde, and there are certainly not many centre backs better in the air than Ramos at 1.84m.