- Dark Heart is -1 AP/+9 MP for you and -10 MP for someone else; suboptimal when compared to Advocate Blessings, which are -0 AP/+7-22 MP for you and -1 AP/-2 MP for the Advocate.
- Soul Ice requires another person who has Pact support to be worthwhile, since WMs suck at making it.
- Potions require time and resources to make, and fonts can be trapped/need maintenance.
Reduce cost of Hellhounds to 15 MP: Hellhounds are supposed to be the Demon counterpart of Judgemasters, boasting similar statlines and a 60 CP upgrade to improve their stats, but due to Caretaker's Gift Hounds cost an extra 5 MP to summon. Their stats certainly don't justify the 20 MP cost: Hounds have +10 health, a 15% chance of dealing critical damage and are immune to fire, but JMs have +3 damage, +15 MP, can attack flying targets and can change their damage type. And regardless of stat differences, for every 3 Hounds you summon a LS will summon 4 JMs, even if you can upgrade yours with mutations (which they kinda need to avoid being underwhelming, another issue WM pets have). Which leads me to my second point...
Reduce cost of applying mutations: Mutations are a neat concept, but they're prohibitively expensive for what they do. Sure, you could randomly give a Hound +10 health... or you could summon another Hound. Wyrm Masters are supposed to be ever-shifting vectors of mutation, but there's rarely a moment when mutating a pet is worth it more than just making a new one. Reducing the cost of applying a mutation to 5MP and Nether Grafting to 10MP sounds reasonable to me, and would make upgrading pets more appealing.
Apply mutations when rejuvenating: Even if you've spent a considerable amount of MP to give a Hound mutations, you usually need to keep paying MP to ensure it doesn't go poof. That's an extra 20MP you have to pay periodically, per Hound. Making it so rejuvenating a pet also applies a random mutation free of charge would hopefully alleviate the feeling of having to babysit your most improved specimens. Another idea I've seen around is the opposite, where applying a mutation also rejuvenates the pet, but given I just proposed 5 MP mutations it'd be one or the other, and I personally like my proposal better. If that gets rejected though, I'd also be fine with mutations causing a rejuvenation (like a demonic Faunabond).
These ideas don't really improve the WMs' issues with gaining MP, but I think they'd help them spend it more meaningfully and alleviate the feeling of constantly struggling to make ends meet. It's possible only some of these proposals will make the cut (or none of them), but in any case here they are, so thanks for taking the time to read them.