Yeah the only way to avoid the invincible thing would be a still version only, even engine killing but thrusting on momentum could let you get across a system without being able to be targeted, with no time limit like fuel. Especially with snubs only getting around a minute cloak time with a light cloak...to give them an unlimited radar invisibility and the ability to travel at the same time...just wouldn't make sense.
Even though I am not looking forward to the cloak changes (at all), it seems like this will all be negated by the fact that if cloaks go ammo based with cloak batteries, cargo holds are going to be freed up from using fuel, so in theory even a freighter or transport could use a cloak and still smuggle goods. Although I'm not sure on what ships will even be mounting what cloaks after this due to the numbers thrown around.
But I will admit I'd rather see a 'still' version of the power down and have cloaks remain as they are, than ammo based cloaks that will force fixed times and limits to what you can get out of a cloak.