GOOD
1.) PT (214A) doesn't have the hit-grab on the first spin, but it knocks down on the last hit. Worse for followups, better for Ring Out.
2.) ABB/BBB strings present; can be used for poking or whatever?
3.) 22K doesn't need a Counter-Hit for followups. This is mostly important for 214B+G and wall combos.
4.) Throws cause "chip" (so his normal throws do slightly more damage), and can be cancelled into another throw (including low ones).
5.) Similar to above, Berserker can cancel the first hit of PT into 214B+G!
6.) 6B+K if charged/CH allows an OTG throw attempt.
7.) 1K is better. Also combines with 2A+K (which Astaroth also doesn't have) for really good lows that catch step in both directions.
8.) Berserker gets much more damage from his B command throw (214B+G, 22K, 22/88B). It's difficult and requires you to step in a specific direction to combo, but is highly rewarding.
NEUTRAL
1.) Berserker's throws are different, obviously. This doesn't affect 'normal' throws much, except that his ordinary A grab can RO.
2.) 1B doesn't "lift" downed opponents.
3.) No air throw, but beefy OTG throws. Less stable damage, but greater potential damage in similar situations.
4.) Charged 5K doesn't have a grab. Better RO, worse oki (though you can run up for an OTG throw attempt)
5.) 3A+B doesn't do the "lift"; it just flips overhead all the time. This means no followups work (like PT), but you won't risk running off a ledge.
6.) 4A+B doesn't "hug" when charged. You can Bullrush, though.
7.) 214B+G can be followed with 2_8A+B to knock the opponent sideways. Mediocre damage and no oki, but great RO potential.
BAD
1.) Berserker is wider than Astaroth. Might be my imagination, but I swear his step is even worse.
2.) Berserker has slightly less reach overall.
3.) Charged 5B is not plus, so you can't do frame traps with it.
4.) 3B+KB isn't available. Not a huge loss, but less damage is less damage.
5.) Berserker's potent 214B+G weakens his grab mixup, as he lacks a strong A-throw like Astaroth's (and has a flash that makes it easier to react). The fussiness of his combo, combined with the weaker A/B 50/50, makes Berserker less consistent in this regard than Astaroth.