Well, speaking from the republic POV...
I can get to all of the zones with my un-stealthable character and I only *have* to fight two trash packs which are not mission related.
One pack outside the H4, one pack covering the exit of one of the normal mission entrances.
Stick to edges, jump on ledges and hide from elites.
You can't do the same on the imperial side?
You can definitely get lucky, and the patient who can stand waiting for elite pats are definitely rewarded. But if you happen to get knocked off your bike (because you WILL aggro things) some places are so densely populated that you'll probably have two packs actively chasing you, and no where to run without aggroing a third. Get unlucky with the bike knock-offs and it's a real pain to get around.