Full hones would be weird as you'd have everybody throwing quick hits all the time. And Garnet spamming Odin.
I think r5 for <4 stars skills, R2 for 4 stars skills, R0 for five stars skills would be reasonable?
Level 50 might be enough, and it would mean Warrior / Knight at full power
I'd vehemently disagree with capping off at L50 exactly because it'd inflate people who suck because they don't get Memory Crystals. They've been a huge part of the metagame since they were introduced and the current meta has most main parties already capped in at L65. L65 cap I might even agree with, since so few people have MC2s out in JP, but capping off at L50 doesn't even allow the PCs to grab Record Materias, and all characters who break level caps get at least one associated with them.
That said, I wouldn't even -allow- 5* abilities if taken at global, since pretty much zero people have been able to -craft- a single ability in that list as of now. Their orbs aren't even farmable, for chrissakes. For weaponry, I'd allow L20 5* uniques (due to character uniqueness clause, even if getting -any- of them is a complete crapshoot) or a generic 5* weapon in case they don't have SB equips + generic 5* armor of their type for the sake of streamlining. But this is theorycraft for a stat topic that will hopefully never see the light of day (the very allowance of skills is a bit of a legality issue, since not much of it is -actually- unique, and a lot of it is unique simply by current default. Allowing all abilities within the given skillsets is an idea, but also flies in the face of how the DL handled most skillsets of this ilk).
Ah, good point about hones on the 5-star skills. Since those aren't farmable, the rank they can be honed to can actually be counted. For all other skills, I'd just assumed max honing.
As for weapons/armor... if you allow full choice, I'm pretty sure it works out to about the same as what Snow listed. Almost all characters want their Soul Break weapon/armor over everything. Though I suppose there's a few instances where they want one of the generic Soul Breaks, and that's probably not the best idea. Also, Lv20 for 5* equips is certainly reasonable, though that information is less readily available, and simply allowing max level would make the stat topic easier (and it would even out if given to all characters).
Any view that wouldn't allow Record Materia (and those are the most unique part of the game) doesn't sound like a good way to show off the game. Gotta have my Brainwashed Kain.
You -could- just take all characters at Lvl50, but assume they have broken the level cap so they can use their RMs. Though that doesn't really reflect how the game is going recently.
Here's the spreadsheet I've been looking at to consider all of this:
https://docs.google.com/spreadsheets/d/1p6iMuCSWr_2QLQVxnhYjz5og6oOx0CfgCCNb_z4JCPY/It even has a damage calculator...