Hello there Tenno.
Preface: I noticed certain frames work with each other quite well, and I decided to pair these up. In the future I thought I may include the best 3 man teams, and the best 4 man; however, this is what I thought up so far. Enjoy!
Exterminates (including Bosses) and/or Survivals
Limbo & Valkyr - Team invincible: These two complete exterminates, bosses, and Rescues with no issues. Limbo stays in the void, and banishes Valkyr when her invincibility is going to expire. When Limbo's riftwalk is going to expire, Valkyr can prepare to rez him.
Trinity & Nekros - Team Infiniscavenge: Trinity can provide health and energy for Nekros to fear, scavenge, etc.
Ember & Nova - Team supermassive blackhole: Nova prepares the opponents, and ember decimates them.
Mirage & Mag - Team Bullseye: built to take down bosses, Mag marks a target and Mirage with her damage buffs can take it out.
Defenses and Interception
Loki & Vauban - Team Melee Defenders: Complete defenses/mobile defenses with a Loki disarm, then the melee opponents fall into Vauban's Vortex
Nova & Volt - Team Speedhax: Nova uses her slow, and Volt speeds the team up, and provides a hitscan shield making their damage amazing, and mobility unmatched.
Excalibur & Frost - Team Frozen Blades: Excalibur can blind and unleash his javelins while Frost can freeze / slow and provide cover.
Limbo & Mesa - Team Banished Bulletstorm: Limbo banishes Mesa and Mesa rains bullets. GG.
Nyx & Saryn - Team Pills and Potions: Saryn distracts, Nyx lets out chaos, Saryn melts, and Nyx defends. They do well at everyday missions.
Oberon & Rhino - Team Stomp: this is a good all-around team for higher levels due to their stomp/reckoning and good defenses.
Ash & Banshee - Team Ninja: They specialize in stealth and silence. Ash can take out an entire room with Blade storm, or Banshee can help them sneak past in silence. Typical ninja stuff. (Note: Loki could replace either of these)
Hydroid & Zephyr - Team sharknado: now with more tornados and tentacles. I'm not explaining this. Nope.
Good additions to almost any duo team:
- Limbo - He has the ability to go into the void and banish an ally (to include rescues)
- Trinity - Free heals and energy.
- Nekros - Extra loot. Duh.
- Volt - Speed boost and the shield of awesomeness (hitscan and extends phage etc to infinity.)
Please note this is all my opinion, and I welcome the opinions and insight of any players, so PLEASE discuss. Have at it! 3s or 4s team ideas? Let me know.
Update 15.5 Added Mesa team to Defenses