Well people are going to jump into this thread and tell you there is no honor in the MA. That, however, is not true for everyone. Neither of the tactics you've described is unfair or dishonorable.
What you describe as a "cherry pick" doesn't fit my definition. A cherry pick, in my opinion, is when you pick an already engaged aircraft who is essentially defenseless against your attack. If its just you and the other guy, then it can never be a pick because he knows or should know you're there. Especially in the example you give where the enemy is essentially lifting off the base to attack the agressor. The only dishonorable move (again in my opinion) in the first example would be to kill the guy while he's still on the runway and essentially defenseless. Once he's up and cleared the base boundaries, he's fair game.
There's only one person responsible for ever being roped and that's the guy who blew all his speed trying to zoom up to the enemy. Following the enemy up like that is, at best, a calculated risk. You're betting you can get to him before he can turn the tables on you and vaporize you before you can recover. Best practice in the example given is to let him be the agressor until you can work down his E to a point where the tables are a little more even.
Most of the time, when I'm the Jug in the scenerio you describe, the first plane to lift off and defend the feild is either an LA-7, or a Spit16. Either of these planes, flown by a sligtly below average stick, has the ability to equalize E with me within 60 seconds of my first pass. So, as a Jug pilot, I know they better be dead within that first minute or the Calvary is going to start launching off that base in droves before I can recover my energy. While the Jug is a pretty fast plane, it doesn't have the get away ability of the 51, 109k, or 190d because of its lack of acceleration and/or sustained climb rate. If they aren't dead in that first minute, I can sustain the fight to longer duration but I will have depleted and E advanage I may have had and now have to consider exit strategies as the enemy is likely launching off the base like a bunch of fire ants who just had their hive kicked over. Also the enemy has the advanage of unlimited lives. No matter how many I kill there's infinite numbers of aircraft which can lift. I will generally stay in this fight until one of three things happens. 1. fuel/ammo depleted 2. Damage sustained to my aircraft impedes my ability to fight. 3. So many ants come out of the hive that I need to fall back to a position where I can fight them off.
Anymore, what really happens when I approach a quiet base looking for a fight, no one on the other team sees my lone con as much of a threat and doesn't bother to launch an airplane. Usually I orbit the base waiting for the ants while some guy spends 10 minutes shooting at me in an 88.