Actually I felt that Jake was short of spell slots compared with Matt. Matt has 22 slots of levels 7, 8 and 9 which can be boosted immensely and flexibly with. Going full-out with Epic Spellcasting Jake can only manage 9 slots.
I was thinking upgrades are priced on the difference in USP. I was thinking of him taking a USP 24 spell and boosting it by +3 to get a USP 27 spell at a cost of 3000 gp extra. An oversimplification, but it shouldn't make a lot of difference.
Heavily mitigated spells will be a pain if they involve expensive components and/or lots of xp payments. They through off the wealth by level guidelines, and could prevent characters from leveling up when expected. Item crafting feats will also screw things up. I don't know if you have a rule of thumb for handling such things. I liked to use "wealth audits" of characters to ensure their wealth was appropriate to their level, but I never found a good way of modifying the numbers for characters who made their own items (who would thus have less xp but more cash) or who used lots of
limited wishes and what not. Well, we never got to those levels of play, so it never came up.
My formulas indicate that a player who stays a level behind the rest of the group in order to earn more xp in order to spend them on stuff will be able to spend about 3000 xp per level without falling further behind. That's with xp assigned according to a formula that takes the square of CRs, but otherwise as in the PHB. With the official exponential xp system... well, it's broken, so it is hardly worth discussing. But players get a lot more xp for being a little bit behind. This is worth a thread in its own right!
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Just "Jacobean"? Or Jacobean Press? Jacobean Publishing?
I've posted a thread in Meta asking how this would be accomplished.
[edit2] Jacobean Publishing it is... but it sounds like Morrus doesn't want to sell any more forums. Did Deborah Balsam from Dog Soul get in touch with you? I bet she'd let us use Dog Soul's forum. I know her- she's good people. Jacobean Publishing could be an imprint of Dog Soul.
[edit3] In
Pricing robe of the archmagi I complain about the discrepancy between the DMG price and price when you work things out. The robe should be 130,500 (91350 after the alignment discount), but is only 75,000. I'm thinking that alignment restrictions are not appropriate for PC created (or improved) items; they don't reduce the utility of the item in any way. They are better for equipping villains with.
I'm thinking that as a general rule, non-standard items should be priced according to Skip's formula, without faux restrictions, and then a fixed, ad hoc discount applied to reconcile things with the DMG.
For a robe of the archmagi the ad hoc discount would be 55,500 gp; the difference between the formula price and the book price. If a player wished to improve the item to give a +8 armor bonus, SR 32, +5 resistance bonus on saves and +4 spell penetration, they'd calculate the cost as follows:
SR 32 is 200,000
+8 armor bonus is 64,000 x 1.5 is 96,000
+5 resistance bonus is 25,000 x 1.5 is 37,500
+4 bonus vs SR is at least 24,000 x 1.5 is 36,000
(I'm guessing bonus squared x 1500)
Total: 369,500 - 55,500 = 314,000
The augmented robe would still retain its alignment restriction, but wouldn't get the full 30% discount for being restricted to a particular alignment. And it has to pay the surcharge- or most of it, the ad hoc discount applies. If we followed the weird pricing scheme that the
robe of the archmagi followed (no surcharge, 30% discount) it would cost only 219,100 gp.
I think this is a good way of remaining faithful both to the section on pricing magic items and to the description of the robe.
Oh, and SR 32 is probably the highest we should follow the (SR - 12 ) x 10,000 formula. Above that we should do something different. Although I still disagree with you on the use of a cubic formula. It should be quadratic.