So I finally sat down and looked over the categories - all 244! :-D
I dropped them into an Excel spreadsheet and went through roughly grouping them. Most of the groups are purely for sorting purposes, a few did impact on naming conventions. I'll try to broadly cover what I'm thinking and why. Hope I get some feedback!!!
I've included breadcrumb style names for a few categories, but these aside, I don't think we want extensive sub-tiered categories. I actually looked at some and the categories were looping X includes Y which includes X which includes ... Parent>Child>'Grandchild' is as much as we want. Might rethink this after I've slept on the idea though ;-)
The largest group is the list of categories I'm proposing we remove. Frankly most of the 42 redundant categories have very little, very specific, and possibly very dated content. Things like armour are outdated and I think the entire categories should be scrapped. I've been pulling it out of the pages I've tweaked - something I probably should have checked first! Minecraft or TB's Hat are single topic categories. We have pages for those, we don't need categories too. Things like Cats or Bikes are IM(NS)HO superfluous they fit perfectly well into higher categories (Pets | Vehicles) and we don't need a sub-tier. Mech play style classes also seem redundant to me - You can supercharge a Warthog or lumber a Saucer with the right\wrong parts. Interviews and riveting TV are single item topics. Should be fine to consider them misc\other etc content. I actually like the VIP Shop category but for now, Coffee aside, pretty much everything in the VIP Shop is seasonal, and those items should be classed elsewhere not as VIP.
The unit categories are where I think the biggest changes should occur. I'm still undecided whether we should delete a bunch of these - Credit Boxes for instance isn't a particularly useful category - pretty much on par with Cats or Bikes. Wouldn't it be just as easy to include those pages in socket powered or simply units? Similarly, do we need a Bucky category? Yes I'm aware we have a handful but why not use Units>Vehicles - I doubt we'll see a tonne more Bucky alternates\reskins! And while I mention it, rather than saying a unit is in categories: Units, Bucky, Vehicles, ... why not just Units>Vehicles>Bucky? Most units should only need 1 descriptor. Ultimate, Missile or Unbuildable PvE units would be exceptions.
Is anti-ground useful at all? Pretty much everything is! Anti-air is possibly useful, but is that for specialist units e.g. Seeker or HAAT, or for all units that can attack air so Jumpers, Jokers etc? Currently seems to be more the latter, but only 34 pages, which seems rather few, then again there's about 50% more than I actually counted as AA capable so ... What about no-attack\non-commandable? Useful or not? I tend to think no-attack fairly obvious and non-commandable is basically a few of the infantry + "buildings".
Most of the rest of the groups are largely leave as is, maybe check tiering. General I think should include buildings (outposts, forts, anything else added) but this class should not include buildable stuff! Drop Systems should be renamed Drops - items are dropped, we're not focusing on how\why things drop. And I'm confused by Tabber. A class for tables?
Rarity should I believe be attached to all items, units, skins etc. I think also noting if an item is retired, unsellable or exclusive falls into this category. NB: My definition of exclusive is that something can only be gotten via restricted means - e.g. buying Alpha Bundle, Using Chrome Client, being a DVIP. It is not a seasonal item. I'd say seasonal and exclusive are mutually exclusive!
Mechs is self explanatory. Again no need to sub-tier categories in this group.
Bundles, pretty much same as mechs - any subjects relating to these bundles\packs.
Collections is something I've ummed and ahhed (hemmed and hawed in American?) over a bit. I think it worth tracking what is classed as a collection but :Category:Gothic will be broader - Gothic Goliath for instance. And of course :Category:Donut is also a pet class. I'd recommend tidying all card stuff up into a single generic category. We now have Greatest Matches, Full Force and Mooncake. Odds are more will eventually be released.
Events could be classed Events>specific event e.g. Ocean's Week\Birthdays. Would that make classing stuff as Seasonal redundant?
Consumable is another slightly fiddly one. Boosts and Cubes largely cover the same stuff - Boosts also includes things like Diamond Bundle and Raptr Attack Pack though O.o Maybe eliminate one? That'be mean Books, Boost\Cubes, and Crates are child categories of Consumable though.
Cosmetic is fairly self explanatory, and on par with units. Cosmetic is the parent class, Pet and Flair the 2 child classes (probably should flip the Cosmetic\Flair page contents since they are confusing and inconsistent with AM - Yes may be a lot of work). Both Pet and Flair have their own distinct child categories. A lot of the collectibles will actually fit here as Pet items e.g. Cosmetic>Pet>Donut (assuming Collection>Donut isn't preferred?).
Game Modes can possibly be tweaked a bit - do we need both PvE and Survival? Are V1 Rules and V2 Rules children of Maps? What of Challenge, Capture Destroy? Oh and Gamemodes should be parent to Co-Op, CTF, PvE and PvP. Haven't thought about this a great deal mind you.
Unit Alternates are another heavy change section. I split them off units in the spreadsheet but classed them as units to distinguish the alt type. Good idea or bad? basically Unit>Alt>Type of Alt. Would mean you'd potentially have for instance Units>Vehicles>Bucky, Units>Alternatives>Cheap, Common, Anti-Air, any other relevant categories?
Do we really need to give gender for pilots? If so why not Pilots>Male\Female? Also any alts should probably be Pilots>Alternatives - currently a bit confusing lumping units and pilot and items all in as alts.
Factions and Misc are pretty self explanatory. No changes, and the groupings aren't particularly important - simply how I was thinking at the time.
Parts\Loadout Choices is the last relevant one. Some name tweaking would be useful. What's a Special for instance? Parts>Special is mildly more meaningful. Items is a loadout thing but this category is being used for a catch-all - VIP Tickets, Crates, Cakes, Books etc :-( Some overlap with Regular Items.
Stats might be useful as a parent class. Most of these are joke stats - style, holiday spirit and hard-core being the only important ones and cake (not included) being an example of a useful stat we're not tracking. Then again we already have Cake so not too important.