FormerlyHemlock
Hero
Spell point systems invariably fail to capture the feel of most literary magic. Ironically, most spell point systems originate as attempts to capture more literary magic since the magic of most literature seems more freefom than slot based systems.
The catch of course is that in actual play, spell point systems don't actually play like that. Instead, a spell point system encourages the player to invest heavily in a single uber skill and to go nova and expend all their spell points in a blast of irresistible power. And this is on top of the problem that all point buy systems have, in that it's almost impossible to accurate price flexible abilities resulting in points of over and under-costing that lead to completely unpredictable tiering and general balance or more often lack their of.
Spell points probably work ok as long as the cost per usage is well capped and the concept of the caster is very narrow - "I make fire" or something like that.
Those are good observations. Have some XP. However, I haven't seen any such Nova behavior in my game. The wizard does tend to lean on Vampiric Touch a lot, but he doesn't overcast it, just casts it at regular level, and it's hardly a Nova spell anyway. He also uses the Chill Touch cantrip frequently, and sometimes Fire Shield. In fact, the only time I've ever seen Spell Points used for a "nova" in my 5E game is when the 8th level wizard was gearing up to take on a fortress ruled by a Death Slaad, solo, in order to get his gear back. He went ahead and raised 20 skeletons + zombies. Without spell slots it would have taken him a couple of days to do that; with spell points he was able to do it in one day by casting Animate Dead IV.
May be relevant: the player in question isn't all that strong on 5E rules or math. It didn't even occur to him to overcast Animate Dead until I pointed it out to him as a more efficient option, which I wouldn't usually do but for some reason did this time. The fact that he, in spite of his weakness at mental math, has no trouble with spell points in general is one of the reasons I don't buy the "complexity" argument. Spell points in no way obligate you to use to spreadsheets to cast spells...