To your points
2nd- Damage output is lower in exchange for heals received. Making keeping me alive less taxing on my healers. If I'm going to do less damage and not receive the compensatory heals, I'd be more useful in Combat Spec for damage output. (not saying you cannot play it, just that it is not as viable).
3rd- I noticed in parses that they were considered physical attacks, I for one always contended that they were elemental damage (tooltips) and recently was told that I was wrong because they can be cleansed as a physical debuff. I will concede I may be wrong in regards to mitigation.
Edit: Checking Parse Log; yes they do apply elemental damage, but can be cleansed by any class as they are not considered a force attack, yet do not apply during resilience.
Force/tech/physical (weapon) doesn't change the damage type. Simply the way damage interact with armor, and in this case I agree as a marauder/sentinel you PHYSICALLY apply the bleeds/burn.
To go back on the 2nd point you make absolutely no sense. Berserk still applies the same group utility as before, and there is absolutely no corelation between damage and heals. Heals are based off your health pool, not strenght/power etc.
Furthermore, I haven't parsed my mara tonight but i expect the HPS drop to be around 40% overall, due to berserk heals remaining unchanged. I very much doubt you are under constant damage on your dps, so at much you will maybe need one or two additionnal heals? If you take constant damage over 10 second, the delta will be around 1k damage that you haven't healed yourself compared to before. Are you seriously meaning your healers are unable to heal 1k?
As said, yep you are slightly softer than before. But you are still way over carnage (or combat since you actually seem to have a sent and not a mara). Combat also do not pull "better" number, its just harder to keep up in many situations. A good annihilation/watchman player will however still keep those number vey close, and still be one of the best dps in the game.
Once more, you are currently blowing this way over its actual proportion.