Vampire spawn have always been a confusing concept. They started, I think, in 3.0 for creatures with few HD and for creatures slain by the vampire's slam attack. Then they became a template. Then, in Libris Mortis, they became kind of a playable class.
They are supposed to be weaker than vampires, but share their weaknesses.
Pathfinder doesn't make them any more clear. Vampires can now create either spawn or full vampires, at will, regardless of their attack (Bestiary 1). Vampire spawn doesn't seem to be a template any more in the Bestiary. Bizarrely, it says use the statistics for a Wight (even for like a gnome vampire? won't this make some creatures ability scores get worse or better illogically?).
If I'm reading this correctly, a vampire could kill a level 20 halfling fighter and recreate them as a vampire spawn with the stats of a wight and a CR of 4. The halfling fighter would basically lose all of their other abilities. This probably makes very little sense.
But the vampire spawn seemed to have gotten a makeover in the Monster Codex. Here vampire spawn are back to being a template. The template allows vampire spawn to keep their class levels. It's a major improvement, but there seem to be some flaws in the template's design. For example, the vampire spawn only gains +2 CHA and no strength. That kind of clashes with most depictions of vampires.
It is also very strange that the text says this template can only apply to characters with 4 or more HD, and the example spawn is a level 2 rogue with 2 HD.
So what is the best solution here? Is it to just use the D&D rules on vampire spawn? To use the template but give it more strength?
Has this been clarified somewhere else?
I'm not sure exactly what your question is. The 'best' solution would be whatever works best for the kind of story you are trying to tell.
For clarity sake, the Monster Codex vampire spawn template, being quite different than the 'regular' vampire spawn should probably have been given a different name and probably should have been given a bit of guidelines as to when to use it ('lesser' vampire, used for vampires of less than 5 hd for example) while the vampire spawn remain generic items.
The 'regular' vampire template requires at least a 5 hd creature. A vampire that uses create spawn on a weaker creature must create a spawn version, and if it is 5 hd or more they have a choice to create a spawn or not. A vampire might prefer to create an easily controllable spawn rather than a powerful potential rival. The generic spawn lose pretty much all their individuality and personality.
Although it doesn't mention it specifically, there is plenty or precedent for creatures that can be different sizes to be presented in medium size, with a blurb on how to adjust for small (basically just make them small and add in the size based adjustments, +1 to hit and ac for example) and certainly it would make sense for a gnome or halfling turned into a (generic) vampire spawn to remain small size.
I thought that spawn lost their personality and individuality as well, but I can't actually find that flavor text anywhere. And I'm not sure it makes sense for vampire spawn to have their ability scores "reset" to a wight's, regardless of what they were before (so, say, someone with an 18 intelligence becomes an 11, while someone with a 6 also becomes an 11, and so on).
Plus, the wight is a great deal weaker than the vampire spawn in the 3.5 monster manual (just look at the ability scores). Was this intentional?
The template concept in monster codex is a lot more attractive, but it removes the idea of a spawn losing most of their personality when created. Now they are just a vampire-lite. Plus, as I mentioned above, the ability score changes don't seem complete (+2 CHA as the only bonus is bizarre; aren't vampires, even spawn, supposed to be somewhat strong). The template also says you need 4HD or more to use it, but the example has only 2 HD. Which is correct?
My question was really how have people resolved all of this weirdness when using vampire spawn? If you disregard the text in Monster Codex about needing 4 HD, I suppose you could decide that a vampire, when choosing to make a spawn, has the option of using the template or the wight statistics, but is anyone actually doing that?
My own thought, without being a Pathfinder v. 3.5 expert, is that the best option is to use the vampire spawn as presented in the 3.5 monster manual, but to craft some kind of a template-lite that applies to their ability scores (so they get stronger, but less intelligent or willful, or something along those lines).
The transformation to a vampire spawn has never been the easiest thing to GM/DM. The only time I've ever used them was when I was just creating them from scratch and not transforming an existing NPC or PC into one.
I'm not sure what your question is. I guess you could run it as written once you decide how to resolve the template HD requirement (whether it requires 4 HD or not).
That doesn't really solve the issues with using the wight's base stats (whatever that even means) if you think the 3.5 MM version is better, or the problems with resetting all attributes to the wight's (or the 3.5 spawn's numbers), or the issue with the template not really changing the base creatures attributes at all (which clashes with the entire vampire concept).
That kind of clashes with most depictions of vampires...So what is the best solution here? Is it to just use the D&D rules on vampire spawn? To use the template but give it more strength?
Vampire spawn are disposable minions, animated corpses with no free will. It sounds like what you want is a true vampire.
I thought that spawn lost their personality and individuality as well, but I can't actually find that flavor text anywhere.
It doesn't actually say it, but the stat block itself strongly implies. All the bestiary vampire spawn are the same, with the same skills, no class or class abilities, only speak common.
Like the wights, which also create spawn, a vampire spawn doesn't care (and probably doesn't know) what it was before it was created.
If that doesn't 'fit' your game or how you want vampires to work then obviously do something different. You could use the pathfinder template version. You could use the 3.5 version (modified to fit with Pathfinder rules.) You could come up with something completely new and different if you desire.
If you are asking what the 'right' way to do it without using optional rules, that would be to use the vampire spawn from the bestiary, based on the wight stats. But the right way for your game is whatever is the most fun for you and your players.
Spawn can be created with free will if the creator goes over their HD limit, and they can otherwise be freed, so that would suggest to me that they still have their ego, they're just firmly dominated by the vampire that created them unless they're freed. Obviously do it however you think it should be done though.
A spawn's free will/mental capacity, like that of any NPC, is pretty much up to how the GM wants to flavor that particular vampire. You can have them behave as though they were charmed but otherwise lucid, as dominated drones, or as bestial runts who would run amok if not controlled. That's part of the fun!