I've tossed this around with a few people in chat at various points in the past, but might as well make a topic about it. This is what happens when I don't have work.
Anyway, the basic idea is that in Fire Emblem (not the only game this may apply to, but the subject of this topic anyway), some characters join at much higher or lower levels than others, and taking everyone at equal levels does nothing to reflect this. Unlike most games where levels even out as the game goes on (Suikoden, for instance), in FE this doesn't happen naturally; if Nino is given the same treatment as everyone else she will still be behind on levels at the end of the game.
The basic argument is that it is unfair to give underlevelled characters more resources and overlevelled characters less. In PS4 we take everyone at equal experience (after they join, at least). Logically in FE we should do the same. This means giving everyone equal numbers of kills, as well as Bonus Experience for the games in which it applies.
I am aware there are arguments for equal levels and have myself made them - namely that it's arguably a better use of your resources to catch underlevelled PCs up. On the flipside, doing so does cause the rest of your army's levels to suffer slightly, meaning that the level disadvantage always exists in some form unless powerlevelling occurs and this is usually not considered.
Anyway, this topic exists for two reasons. One is to discuss the idea in general. The second is because I have a poll/question of sorts.
The main reason that I don't yet vote this way is because it's quite a bit of work to figure out what level everyone "should" be at. Still, I'm quite willing to do it, when I have some free time. I'll be focussing particularly on FE9 and FE10 first, because those games reward underlevelled PCs much less in the Exp formula, i.e. level differences are more important and last longer (GBA games give +3.33 Exp per level underlevelled, the Tellius games give only +1.5). Of course, these happen to be the games with Bonus Experience.
Now, as my rambling comes to a close, it's obvious that for regular, Combat Exp, PCs only get Exp in maps they actually exist in. I mean, duh. For Bonus Exp, it's less obvious what the right thing to do is. Two options here:
1. After each battle, take the Bonus Exp and divide it among the PCs being used who are currently being used and available. This means that PCs who join late will get less Bonus Exp overall because they only get a share of Bonus Exp obtained in later maps.
2. All PCs who are used get an equal share of Bonus Exp, and if they aren't available early it is stored up for them.
Now, for FE9, I find myself leaning towards #2, but am certainly open to #1 as well, since #2 arguably wastes a lot of Bonus Exp while it sits around if you're waiting for, say, Largo. For FE10, #2 is problematic because you use much more than just a single planned party of 10-12 units, so it isn't really clear what "all PCs who are used" even means. This makes me lean towards #1 for FE10, but taking #1 in its pure form leads to relatively silly situations where a PC may be screwed out of a large amount of Bonus Exp because he or she misses one map after you get a particularly large amount (particularly egregious for Geoffrey et al. after Geoffrey's Charge, since that map is worth a massive amount of Bonus Exp and Geoffrey's knights have to work extra hard to get it). I dunno.
So yeah, any thoughts here would be appreciated.