Captures easy my oscar.
Yeah, IF you have the right number of guys, IF you have the right guys in the first place, IF those guys are all committed to the capture, IF those guys can coordinate properly, IF they can keep the defenders down, then yeah, MAYBE then you can call it easy. The successful captures I've been in on have more or less had the same thing in common: The enemy doesn't have anything in the air.
That's how a base capture works: NEUTRALIZE ENEMY AIR DEFENSES. As in, vulch, cherry pick, kill the FHs. Don't let anything up because it's going to fubar the whole thing (ONE fighter in the air that breaks through cap to the troops can screw the pooch) A base capture isn't SUPPOSED to be a fair, even furball with both sides allowing each other to up and join in the fight. It's dirty, it's brutal.
There's nothing wrong with this system. If the attackers can coordinate their assault so well that they can set up an air-tight cap, then the DEFENDERS can coordinate their counter-attack from another field. NO ONE here has said the Defenders had to lone wolf their way over from a satellite field. That's THEIR choice.
So maybe instead of trying to change the dynamic for attackers you should look at changing the defenders'' approach:
1) DON'T UP FROM A CAPPED FIELD IF YOU DON'T WANT TO BE VULCHED. JEEBUS! How many times has this been said already?
2) Don't go in all gung-ho Lone Ranger style thinking you're gonna break the cap by yourself. Do what you need to do to organize the defense. Make a mission if you have to. Guess what, if you coordinate the counter-attack you won't have the meaningly slow trickle of guys into the fight.