Just like the title says, what are the lists you need to plan for playing against at a tournament?

I assume:

Brobots

Palp Aces (and variants)

TLT spam

What are the others?

Four-ship Rebels, likely including stresshog, regen, or both.

These are some of the squads you might see in the next week (before Wave 8 lands):
Poe + Miranda + escort (regen Rebels)

Han + Jake

Firespray/YV-666 + two Y-Wings with TLT

Chewbacca + Leebo

Mixed TIE swarm (TIE fighters, TIE/fos, mix of named and generics)

Corran + Dash

Whisper + Oicunn

BBBBZ / BBBB

Brobots

Specific ships to be prepared for:

35 point Soontir Fel

crackshot swarms

Poe/Jake/Kyle is getting fairly popular lately as well.

In the last two tournaments I didn't play the same list twice, so it's hard to plan. There is a lot of stress floating around so that's what I try to mitigate. A y-wing with R3-A2 us almost too efficient for a rebel player NOT to take.

As I see it, these are the most common archetypes (looking at the top 20% of players in tournaments of a decent size (20+ players)).

Imperial

Palp aces

Lambda with Palpatine and two aces. The most common aces are Vader, Soontir, Whisper, Carnor and Omega leader.

TIE swarm

6+ TIE Fighters, with or without Howlrunner. Both classic (Academy or Obsidian) and Crack shot (Black) variants exist, although Crack shot is more popular.

Ace and mini swarm

An ace (see Palp aces) and a few (usually 4) TIEs, following the same pattern as the TIE swarm.

Decimator and Phantom

Self explanatory as for the ships. Decimator usually has Palpatine on board, and the Phantom is almost always Whisper.

Rebels

Rebels are a bit harder to categorize since they have a lot more viable ships than the Empire. Thus the number of combinations is much greater. There are a few that are easy to define, though.

Poe with friends

Poe is extremely popular at the moment. His companions vary, though, but are usually some kind of toolbox alphabet soup. Stresshog is frequently seen.

3K

Three K-Wings, two Wardens and Miranda, all with Tactician.

TLT spam

Four Y-Wings with TLT. Sometimes one Y is replaced by a HWK-290.

Z swarm

Eight Z-95s, four Talas and four Bandits. It has lost in popularity but still sees play.

Scum

Brobots

Brobots are still going strong, although they come in new flavors. Crack shot and Glitterstim seem to have replaced VI and Inertial dampeners as the most common configuration.

TLT spam

Same as the rebel version, except it usually employs Unhinged astromechs.

4 StarVipers and Scyk swarm are really popular right now.

4 StarVipers and Scyk swarm are really popular right now.

Sarcasm detected.

4 StarVipers and Scyk swarm are really popular right now.

Stop joking

Palp with Ceptors

palp with ceptor and phantom

Triple ace

Poe and TLTs

TLT-spam

well, 9\10 lists are PS8+

and that makes me sad.

I keep seeing a lot of Poe/Dash where I am. But that might be a local thing. The Palp/Aces combo thing is popular where I am as well.