You should only use Collect Bounty when you want to hit a frontliner and the target is not stunned, as it has a higher critical chance than Finish Him. Flashbang is also another option for when you need to stun an enemy if your other team members haven't done so already. Next, we have a Bounty Hunter who will usually just pull backliners to the frontline using Come Hither and then use Finish Him to deal massive damage to any stunned enemies.

As their dodge chances are quite high, it is for this reason that people prefer to simply take a Bounty Hunter or Occultist so that they can deal with the backline easily. However, as an alternative, if you have a way to deal with the opposing backline outside of pulling them to the front and beating them with your own frontline, you can do something like run a Plague Doctor with the ability to stun the backline and hope that they don't dodge. For this reason, taking a Bounty Hunter or an Occultist to use their skills that allow them to pull backline enemies to the frontline is usually a good idea. Many enemies that are in the backline are very fast and can cause your team to have a high stress count if you don't kill them fast enough.

Having at least 1 backliner that pulls or a way to deal with the opposing backline.

What you do with these frontliners is also very fluid: You can have a team centered around buffing a Leper so that his low ACC isn't much of an issue, or a build centered around stunning the entire enemy team with a frontline Hellion and a backline Plague Doctor. Generally, however, this will be either a Hellion, Highwayman, or Leper, due to their very high damage output. This one is a little bit more fluid, as you can have many different classes take up this role.

Having at least 1 dedicated frontliner that deals damage to enemies'.

This doesn't mean your party needs a healer, however it is highly recommended you take one for regular parties. The preference on taking which one depends on the person, as Occultist has more utility while Vestals have a higher chance to actually recover the health of your party. This will usually be a Vestal or an Occultist, as their backline capabilities are greater than that of a Crusader or Leper, and their heals can recover the health of your party by a much higher amount.

Having at least 1 dedicated backline that heals the party.

Ectoplasm darkest dungeon reddit