Use both superhero and villain strikes
Notice as Spider-Man uses both his red and blue/black suits, his alignment meter will progress toward his good or bad side respectively. Take a look at the photo in the lower left-hand corner of the screen as well as the alignment meter in the pause menu. While the alignment picture is displaying the red and blue suit, only superheroes will aid him, and conversely while the black symbiote is displayed, only villains will help. As long as the picture is one color, it does not matter what suit you use until the meter color crosses the middle. If you maintain a very close middle ground, you can effectively utilize both the superheroes and villains (although not at the same time.) Strategize by getting both red and black points until your alignment meter is precisely in the middle. You might notice as you defeat one enemy using a suit that Spidey's picture will change in the lower left hand corner of the screen. Even if you have a hero summoned, if you quickly switch to the black suit and defeat more of the enemies until the photo changes, that hero will still stay with you until you dismiss him or your special meter runs out. The same holds true for villains and switching back to the red suit. The alignment affects whom you can summon, not who you have already called in. Use this strategy to defeat your enemies, get the most experience points, and unlock all the moves.
Alternate costumes...