"Avoid" is unusable. I've never once used it after familiarizing myself with it after it got added to the game. The problem with Avoid as-is is two-fold;
problem #1: any ship so dangerous that you need to avoid it, your fleet is probably going to avoid anyway.
problem #2: any ship so dangerous that you need to avoid it, the enemy fleet is probably going to stick to.
So Avoid is useless. It is effectively just a retreat button that wastes CR by not having your ships actually leave the battle. The use-case for Avoid is when the enemy fleet has a lynch-pin ship that you're saving for after its escorts have been picked off, and it does not achieve that in any functional way because it effectively renders all of the ships escorting the Avoided ship invulnerable by sheer weight of their proximity to it -- which is the opposite of what you want Avoid to do to the Avoided ship's escorts.
So! Replace it with "do not engage". Your ships automatically pick enemies they think they can handle to engage, and when picking they simply do not pick the ship marked as such -- even if they normally would. Frigates & destroyers should already be doing this for cruisers & battleships, so what this mainly does is instructs your cruisers & battleships to focus the enemy's same-size ship's escorts before attempting to take the escortee on.
Of course, you have to actually kill the enemy fleet in order to win the battle & the goal of the command system is to reduce micromanaging not increase it, so we attach the (yet) onto it. Once there are no more DNE targets left, your fleet starts picking DNE targets to engage, prioritizing the weakest, which since the weakest is AFAIA a universal calculation (a kite & a falcon consider the same ships equally as threatening?) naturally turns the late stage of a wolf pack battle where you DNE'd the enemy's Onslaught & a Falcon until you cleared their frigate escorts into a dog-pile on the Falcon, and then a dog-pile on the Onslaught -- without needing any input from the player after DNE'ing them at the start of the battle.
Now, that leaves 2 use-cases where something similar to Avoid would be useful but you can't use Avoid for it; when you have an evenly matched fight that you don't want any help with, and when the enemy has something so inescapable that instead of just leaving it alone so it can run ur fleet down at its own discretion u would want to keep it busy as much as possible while ur fleet mops up the escort & gives u better chances in a dog-pile. To that end, we attach the (unless told to) onto it. If you DNE a target and then order one of your ships to attack that target it doesnt remove the DNE, it just clears that ship's list of engageable targets of all targets except for that one, and then tells it to go do whatever it would do if that ship was the only enemy left & there were no DNE order. If you have a fleet of unshielded Hounds & an Eagle & you DNE an enemy Medusa loaded down with Phase Lances & Ion Cannons & Atropos, your hounds should naturally avoid the Medusa bc its a huge threat to them while the Eagle runs it down. If you have a fleet of hounds & 1 vigilance with ion beam going against a fleet of murceries & 1 onslaught, DNE'ing the onslaught & ordering your vigilance on it should cause your vigilance to run screaming from it every time it turns about on it (causing the Onslaught to not be focusing on the rest of your fleet), and when the onlslaught doesn't turn about on the vigilance it should be poking it in the butt with its ion beam flaming it out (and against causing the Onslaught to not be focusing on the rest of your fleet), effectively shutting it down until the frigates are cleared enough for your fleet to dog-pile it.