The Sha'ir (Dragon Magazine 315) is a infamously fiddly and obtuse class to use, made worse by a dispute in how it's even meant to work. First i feel like i need to point out the Raw issues here. The Sha'ir keeps the ability to cast a prepared spell for a number of hours equal to it's class level. The rules say that the power to cast the spell remains in the Sha'ir's mind until the spell is cast or until a number of hours pass at which point the power to cast the spell "dissipates harmlessly".
People can't seem to agree as to if the spell slot can be refilled afterwards or if it's wasted and disappears as if you had cast it. The argument for the "Sha'ir Shuffle" is that the spells don't follow the typical preparation rules and never explicitly make a connection between the number of spells that can be cast per day and how many spells can be retrieved. The argument for people that say that spells disappear point out that the retrieved spells section makes reference to how a wizard's prepared spells work and thus should disappear.
Needless to say that spells vanishing and being unusable makes the class nearly worthless at low levels and a worse wizard at high ones. It means that you need to stay in the class for 8 levels or more before jumping into a prestige class, and that you'll probably never be able to use all of your spells during the day. Granted the versatility of the class makes it ideal for dungeon delving gameplay, but being unable to keep spells for any extended period of time means that any other kind of game will render you into a commoner most of the time.
While i would be interested to hear any arguments for which version is more mechanically accurate, i'm mostly trying to find a way to extend the usefulness of spells past their expiration date. Assuming that spells do vanish as if they were cast, what official means are available to salvage this class's spell casting mechanics?
Some methods i had considered are the Echoing Spell feat (SoX) which causes a cast spell to return to you 1 hour after casting at the cost of being 2 Caster Levels lower. While it's a bit ambiguous as to what would happen to it, i would assume that this would mean that you could cast a spell that's about to expire and get it back 1 hour later for the same duration, though this likely runs afoul of the Retrieved vs Preparation issue. Meaning that this feat possibly couldn't be applied to Sha'ir spells at all.
I had also considered the Runesmith (Races of Stone) Prestige Class as an option. The sha'ir makes mention of spells remaining set in the Sha'ir's mind until cast or until a number of hours pass. While the section explaining how spells vanish only makes mention of how spells can only be used for a number of hours before dissipating, one could argue that storing a spell through a alternative method, such as in a rune, would allow you to dodge this. Again this has problems. The Sha'ir arguably doesn't prepare spells, and even if they did its not obvious that this would prolong the spell's shelf life. Though my next consideration might help.
The Alacritous cogitation (complete mage) and Arcane Preparation (PGtF) feats allow you to effectivly count as both a prepared and a spontaneous caster. Alacritous cogitation, though only usable once a day, allows you to cast a spell you know with a empty spell slot. Arcane preparation allows you to use spell slots to prepare spells, and taking Alacritous cogitation lets you qualify. This debatably lets you prepare your known spells ahead of time in a way that dodges the expiration while letting you leave some open to spontaneously cast spells once a day and send a Gen to fetch the situational ones. This in conjunction with Runesmith could make for a powerful combination, assuming that any of my assumptions work and let you bypass the restrictions of the class. However this is pretty steep, this strategy effectively costs 3 feats and a dip into a martial class as well as using a race that has a -2 in your casting stat to function at all, and that same effort could make a wizard that's substantially more powerful.
So i'm left wondering if there's any way to salvage this class short of begging to use the "Sha'ir Shuffle". This class has a lot of interesting mechanics but to even be usable you need to spend way to long in the class proper and can't take advantage of how it synergies with a lot of interesting prestige classes.
How can a Sha'ir avoid spells vanishing so soon after preparation?