Jim is frequently under-estimated, and for two main reasons:

1. Most people play on Standard, where his special ability is not as important.
2. People miss the single most important thing to know about Jim!

The single most important thing to know about Jim is that the particulars about his character make Grotesque Statue super powerful. There are 3 key reasons for this:

• Jim can use Scavenging to pull Grotesque Statues Back
• The fact that =0 shifts the mathematics of the chaos bag in such a way that you are extremely likely to prevail when you get two draws. In fact, since =0, you are very likely to prevail by 2 or more, and since Grotesque Statue goes to your discard pile immediately, you can actually use a Grotesque Statue pull to get a Grotesque Statue back!
• Double the draws means double the chances for tokens. This is less important now with Carcosa out, but earlier it was very important to get to activate Jewel of Aureolus. Now, with Uncage the Soul, this is less important.

Once Jim gets a statue, he is essentially (invincible) [arkhamdb.com

One of my favorite Investigators, if a bit of a sleeper compared to other Mystic investigators.

While Jim Culver has the basics of a good Mystic Investigator, he does not have the longevity of his spells like Akachi or the Sheer Willpower and low health enemy removal as Agnes. Nor does he have the potential of controlling Doom and using it to his benefit like Marie Lambeau. However, how he plays is something more subtle, with the ability to use the Skull token at a constant "0" value in most scenarios. This ability it still pretty powerful for balancing the Chaos Bag in your favor. (Note though you will still have to deal with the effects of what the skull token brings for scenario and even on player cards).

Being a Dunwich investigator as well, he has access up to five out-of-class level 0 cards. This means you have a bit of flexibility of building out Jim how you see fit. This makes him very good in terms of playing him as a strong solo investigator but also an investigator that can slot in well in multiplayer as a support character. And one other benefit is that he has one more health compared to Agnes and Akachi, which does make him more survivable.

A downside to the jazz player is his low agility and having one less willpower compared to Agnes and Akachi. However this is made up with Mystics having ways to buff their already amazing willpower and spells that cover their stats. And while his Intellect and Fight is at three, he is still going to struggle with hardier enemies and high shroud locations without the spells.

If you are looking for an investigator who is provides an interesting challenge to deckbuilding but has a large degree of both reliability and versatility, Jim Culver is your main man.

I've just recently started a 2 gator playthrough of Cirle Undone with Jim. I'll have a deck list to come soon but at the moment it has gone well using the sealing cards as well as Defiance to mitigate the bag in Jim's favor. Most every test so far as long as I can at least match the test value has gone my way. I feel like sealing mechanic may have jumped up Jim's power level by quite a bit.

Jim’s weakness, Final Rhapsody, used to be a rough setback. Now, with the Innsmouth Conspiracy, you can mitigate it. Fill the bag with blessings and curses, draw five tokens, and take much less damage than before.

There’s not much else to say, except that Jim’s Trumpet scales well with more players. More players means more tokens, with four people out it’s likely that you’ll trigger every turn, especially if you bring Olive McBride on the road.

Jim Culver is an investigator whose power level varies wildly depending on which difficulty settings you play with, and that's a big reason why Jim tends to vary so much in tier lists.

For most play groups on Easy or Standard difficulty, Jim is a Mystic investigator with a mediocre stat line and strong synergy with card interactions that involve skulls. Outside of Jim's 4 Will, none of his stats are particularly noteworthy, his signature Jim's Trumpet is a mediocre source of sanity healing, and Jim's primary appeal will probably be 5 level 0 cards outside his class. The ability to treat Skulls as "0"s isn't that attractive when the worst modifiers in the token bag usually cap at "-3" or "-4".

For play groups that play frequently at Hard/Expert difficulty, Jim becomes a functional god of the token bag. Skull tokens are relatively mild in most Standard/Easy Scenarios, but Skulls scale upwards at high difficulties until they're functionally auto-fail tokens, so Jim becomes one of the few investigators who can consistently pass skill test by fishing "0" tokens or skulls out of the bag (with cards like Dark Prophecy, Nksoi Mabati, or Grotesque Statue. When the token bag is full of modifiers like -5 or -8 and you have to overcommit by 2-3 cards to guarantee a success, Jim becomes a godsend. Jim doesn't need a great stat line or level 1-2 cards from other classes if he can near-guarantee drawing a "0" modifier on important skill tests.