A couple observations:
- You should definitely pay attention to this relationships because Morale is a strong factor to your success. "Some say" it's a flat multiplier for all mercenary's attributes.
- Fox is the most popular merc, Steroid has the most problems working with others. Buns is fairly unpopular too. ("Fox & Friends" team: Fox, Wolf, Malice, Nails).
- Freebie mercenaries (including Maddog) don't have any likes/dislikes.
- One thing a bit outside of the scope of this table is that "Loner" trait mercs (Fidel, Meltdown) are both great sector defenders, being both skilled with Explosives (mines!) and both strongly preferring to work alone (morale boost just like from likes).
- Another thing worth noting is a whole set of mercenaries who are Team Players, who will get a morale bonus when working inside a team of 6. List of TeamPlayers: Barry, Grunty, Red, Sidney, Fox, Buns, Ice, Hitman, Raider, Len, Thor, MD, and freebie Miguel, Carlos, Dimitri, Dr. Vincent.
- Some ladies like to work with ladies only. Amazons: Spider, Buzz, Ira.
Amazon is a FLAW (like Unfit). Ira, Buzz and Spider get "low" morale if working with any man and just "good" if inside a only-women team. Macho, on the other side, is just a benefit when at least one girl is in squad, but no decrease when working with just men. Loner is the same: very good morale when solo, just good if inside a team.
- Finally, NightOps also affects morale, but only at night. List of NightOps mercenaries: Lynx, Shadow, Spider, Raven, Static, DrQ, Scope, and freebie Conrad.
- Some mercenaries form natural circles of love. For example Raven+Raider, Scope+Sidney, Fox+Wolf, Spider+Static, Igor+Ivan+Grunty, or Magic+Blood+Ice. If you want to form a smaller team of people for scouting or defence, it'll benefit you if you choose those people to work together.
- For a larger team, especially one to fight many battles, you want a solid starting point, like your main medic or sniper, your actual must-have mercenary, and then follow the relations route while picking mercs of other professions to add to the team.
I think the best "solution" here is "Team Ice": Ice (sniper/SMG), Blood (melee/medic), Magic (mechanic/trooper), Thor (medic/trooper), Wolf (mechanic/medic/shotgun), Lynx (sniper/explosives). Magic likes Ice and Blood, and they both like him back. Lynx and Thor like Ice, Wolf likes Lynx. All mercenaries are extremely popular and don't have any stupid voices, all are fun to work with.
But you can create a couple dozens similarly friendly teams when you follow the patterns of like/dislike, and it pays off greatly in combat performance.
Feel free to post your "love" teams in this thread.