Since my comment about this somewhere else was quite welcomed, might as well share it here.

For example, during rotation we run with the knives and when using utility (i.e. flash, smoke, etc.) need to switch back to primary to not end up with melee in front of enemies when engaging. Game can do this automatically, go to: "Settings -> Controls -> Equipment" and turn on "Prioritize Strongest Weapon".

Bonus points: For those who are using "Q" or similar from CS:GO you will switch only between Rifle and Pistol, even after knife. Also if primary ammo is empty, it will switch to pistol.

Drawback: Active Ultimates (i.e. Chamber OP, Jett Knives) do not count as weapon and after using utility, we end up with primary weapon. But in my opinion, it's easier to switch back to ult after escape rather than each time running with knife.

If some Gentleman/Gentlelady from RIOT will end up here, please make it even more smarter ⬆⬆⬆