Starting with the obvious, narrative campaign board games are to some degree driven by their story. One campaign game I disliked so much I immediately resold it was Bardsung, in which the story was extremely flimsy, and just barely enough to tell the players why they should go into a dungeon. In games with a longer and better story, the question remains how exactly that story is told to the players. Especially when playing with more than 2 players, having to read a lot of text aloud can become rather tiring quickly, and not every board gamer is actually good at reading text. What I do like in Agemonia and Familiar Tales is that they both have an app or website on which you can have the story read to you by professional voice actors. Some games have outsourced that voice acting to Forteller Games, and that likewise works quite well. For me it is always a plus on a crowdfunding campaign if Forteller or other voice acting is available.

The other side of the balance for a narrative board game is the gameplay: How complex is it? Does it offer enough choice and options? It was here where Agemonia turned out to be the better game than Familiar Tales, by being a lot more varied, and being reasonably interesting, without being too complex. A campaign game I tried several times with different groups and never got far is Tainted Grail, but even with the revised rules the gameplay is simply too heavy for what it does. You can get into a situation where 4 players decide that it would be a good idea to all go hunting, and then spend more than an hour to resolve those actions, without that advancing the story in any way. With food being quite important, that happens far too often, and food / resource gathering ends up feeling far too grindy. Every narrative board game needs some sort of resolution system for stuff like combat or skill checks. But the game needs to keep those either simple enough, with just a few dice rolls, or make a more complex combat system which then is only used like once per session for a major battle. There is a particular subgenre of narrative games, which is the boss battler; but the boss battle here is the climax of the game session, with any other systems for resource gathering or skill checks outside the boss battle being a lot simpler.

Another important part of campaign board games is related to bookkeeping. Most board games have systems to manage resources and the like, but only campaign games need ways to "save" the current state of the game and be able to start the next session with the items, counters, and resources you had at the end of the previous session. ISS Vanguard is a campaign game which literally has a book to keep, a three-ring binder with both pages of instructions and binder sheets into which cards are being sorted to show the state of the game. For example there is a page to put "research project" cards in, and rules how to complete those research projects and move the cards to the "production complex" page. Narrative games that offer some degree of choices and consequences of those choices also frequently need some way to keep score of those decisions, and ways to result in a different narrative as a function of choices made. In 7th Continent / 7th Citadel much of the game consists of several boxes of index cards, which serve both as map tiles, action cards, and a filing system that memorizes your decisions. One typical disadvantage of the more complex bookkeeping systems is that in a game with several players, it is hard to share that activity, and you often end with one guy being something like the designated accountant. That makes the bookkeeping part of the game a lot less interactive and interesting for the other players than the rest of the game. An alternative version is veering into the domain of pen & paper roleplaying games, and doing a lot of bookkeeping on character sheets; but one loses a lot of visibility to the other players, and the feel of playing a board game rather than a role-playing game.

The added narrative and accounting parts of campaign games frequently result in these games being recommended rather for lower player counts, like 1 to 2 players. For larger player counts one needs to find a way to split the various tasks, to keep everybody occupied and interested. For Agemonia that worked quite well for us, because there is so much game material that you can easily have different players manage different parts. But I actually have some campaign games, like The Isofarian Guard, that don't even allow for more than 2 players. Keeping everybody interested all the time in a 4-player game is a challenge, and these are games that I never play at my weekly board game night in the local shop, simply because the noisy environment wouldn't work for that.

With my Agemonia group, I might try Oathsworn, a boss battler. Or I could try Nova Aetas: Renaissance, also a very tactical game. Or we could try ISS Vanguard, which is in structure somewhat close to Agemonia, but with some distinctive differences and a science-fiction theme. For the other group, currently playing Familiar Tales, I might try Wonder Book, simply because it is rather short for a campaign game. Or we could try Kinfire Chronicles: Night Fall, but I'm not 100% sure how good that works for 4 players.