my tip for Hardpoint is thus. Know where the points are and move the secure them BEFORE the current one ends.
ive gotten into arguements in league play with other master rank players (say what you want but typically they are far better then the other ranks.) Hard point Is one of the Key modes in it.
the arguement was whether or not to continue to fight for the current objective or move to secure the next one. (We were down by 80 points in at this... point... <.<.... ) the enemy had complete control of the hardpoint and its main spawn, we had all spawned on the opposite side of the map from the hard point with 30 seconds left. The hard point was about to move to somewhere closer to where we had just spawned. So i argued that we should abandon this hard point and fully secure the next one and set up to keep it the full time.
the reason for this is simple. Take the time you have left on the hard point. how long will it take you to get over there? and how much longer will you be fighting for it? What are the odds that this attack will fail (If I am playing by myself i auto assume that my team will fail). but lets say We did take it, for what? the 10 seconds that are left uncontested? while those guys we just killed are setting up at the next one?
My point is, its better to sacrifice 30 points for 60 points. I have won countless games of Hardpoint where my team apparently didnt know what the hardpoint was so i had to do everything. I have had many comeback games in the end because of this strat. its a slow one but it will win it.