Got my tier-list here. Based on approximately 600 games (BGA and in-person)
I'll summerise most character choices
S-tier
Hawk (advanced): Really reliable all-round choice.
Spotter (advanced): The ability to manipulate events are huge in changing gameplay. It can also save players with events (with the correct rules)
Rook (basic): Effectively giving another player a bonus action (even more if you bypass deadbolt or laser).
Acrobat (basic): Effectively an extra action if you pass through a guard. Plus if timed correctly can allow you to bypass alarms or deadbolts for free.
Rigger (basic): Ability to draw an extra tool will help the whole team. Dynamite a useful starting tool as well.
A-tier
Rigger (advanced): Ability to draw a tool for a stealth is costly but powerful. If a team coordinates well then the rigger can activate at the right time and know exactly what items they are paying a stealth for. The only reason this doesn't reach S-tier is because on hard difficulty having one stealth makes this ability very risky or almost useless.
Rook (advanced): I thought this character was really bad at first, then I realised how useful he could be. To name a few examples, swapping with another team member to: save the other teammate, swap a teammate so their ability can be used to assist the whole game, swap so the rook can use their turn to advance forward then swapping back or to bypass certain bad loot cards (keycard, gold bar).
Juicer (basic): Alarm can be used to help teammates or just have a laugh.
Raven (basic): Slow down guard on your floor or help teammates on other floors, 2 range is really good too.
Hacker (advanced): Might not seem too powerful. The token that anyone can use to bypass an alarm from anywhere on the board is really powerful and I've seen it turn the tide of a game, it's also a good action sink to avoid an event. This one just made the A-tier.
B-tier
All these characters are good at what they do but not exceptional. The main reason the acrobat (advanced) made B-tier was because his ability is very good but also very risky and costly, hence he didn't reach A-tier.
C-tier
Raven (advanced): Powerful on floor one; harder to predict guard movement as it goes up though so is generally much less effective as the game goes on; unlike the basic Raven which is useful the whole game.
Peterman (advanced: The ability to open safes on different floors is really cool but it's very subjective whether you get to use it in a game or not (generally better in Fort Knox mode)
Hacker (basic): This one might surprise a few people. On solo mode this character is really good but BB is a cooperative so I have to look at how he helps the team and it's not very well. The hacker's main ability is to move through most alarm tiles without triggering the alarm. The second part is that players can pass through these tiles freely if the hacker is there (an ability I've only seen used a handful of times). The biggest drawback is that the hacker helps themselves, sure they can explore a floor with impunity, but that rarely helps the team get through later. Also the biggest double edged sword is the fact they can't trigger alarms in a hurry; something which I've seen result in a loss because another player is along a guards path (or at least a huge setback).
D-tier
Juicer (advanced): I played this character a lot before deciding it was just bad. The first ability is just a worse version of the juicer, allowing a player to trigger an alarm on their own tile. The second ability is a little better, allowing a player to pick up an alarm tile they are on and remove that alarm. This ability though can very easily backfire, but also the alarm limit is 1 and that alarm is needed to trigger the first ability. In other words the basic juicer does almost everything the advanced one can but better.
