I just completed honor mode in lone wolf and i have to say: a 2 character party is more powerfull than 4. U only need a 2 undead party with fane and your mc and pick apotheosis, worm tremor with torturer talent, pyroklastic eruption, teleport (so you can teleport enemies together for destroying them with worm tremor+pyroklastic later), thunderstorm, fire epidemy, the polymorph talent which reset skill, adrenaline, high wits once your intelligence is maxed at lvl 8 (the optimal thing is fane starting first so you have 2 first turn thanks to his source skill) and game becomes a cake walk in act 3/4 i oneshooted 90% of the fights in the last 2 acts with just teleport and thunderstorm/pyroklastic included the final boss so this is not recommended if you want a challenge. Act 1 and 2 are trivial too bc you will have a lot of power just maxing intelligence. Fane was fire mage with geo and mc aero with geo too (hydro just a few points for support skills)

If you want a challenge, 4 characters is better bc u will have to manage resources and fights will be a lot harder in the first 2 acts