Fantasy Adventure Guilds for RPGs

Historically speaking, the entire purpose of a guild was regulation of goods and services.

Diegetically speaking, Elder Scrolls III Morrowind's three Imperial Guilds for adventurers, the Fighter's Guild, the Mage's Guild, and the Thieves' Guild, which were ALL very clever because they were all implemented by the government, yes even the Thieves' Guild, to control the more dangerous elements of the society by channeling their dangerous behaviors rather than just imposing laws to restrict their more dangerous behaviors.

The Fighter's Guild was implemented to control independent mercenaries and give wayward soldiers and vagabonds something productive to do and keep them from becoming brigands. Membership grants you training, an income, work that is productive for society, opportunities for advancement and a good reputation, etc. The fighter's police themselves.

The Mage's Guild is like the Fighters Guild, but there's the addition of what is considered acceptable magic and unacceptable magic. Now your mages are restricted from doing the "bad magic" to keep their membership. The mages police themselves.

The Thieves' Guild is the most clever. The Thieves' Guild is the ultimate government psy-op. Members are given expectations about what crimes are OK, and what crimes are not OK. This means thieves' guild criminals are less dangerous than non-member criminals who have no such rules. Further, if you're in the thieves' guild and you get caught by the law, the guards will accept bribes and let you go to thieve again. If you're not in the thieves' guild, the guards will NOT accept bribes. Independent criminals and competing criminal organizations cannot compete with the thieves' guild. The thieves' guild police themselves and they police other thieves' without even trying. Additionally, by accepting bribes from the thieves' guild, the government just found out how to tax crime. 

All these organizations are incentivized to keep their charter, which is the document from the government that permits them to operate, by operating effectively. If they go rogue or fail to operate effectively, the government does some culling or some quality control for the members and leaders.

Track the value of money, not the types of coinage

If money in D&D has a gold standard, then instead of tracking the number of gp you're carrying, the number of sp, the number of cp, etc., you just track the value of gp you have instead. Example, 1 cp = 0.01 gp, 1 sp = 0.1 gp, 1 ep = 0.5 gp, and 1 pp = 10 gp (all values based on 5e PHB). So 5 cp = .05 gp and 9 sp = .9 gp. Therefore, if I had 5 gp, 9 sp, and 5 cp, why not just write down 5.95 gp? If the cost of most goods and services are based on GP, then no depth of gameplay is lost. 

Pros:

• Players are already programmed to track only one value for their money by video games, so they don't have to learn anything new.
• Reading that I have 5.95 gp is faster and simpler to understand and to communicate than reading that I have 5 gp, 9 sp, and 5 cp.
• Save time on conversions.
• Simplify your character sheet. Get rid of useless coins like ep, the fifty-cent piece of D&D, and cp, the penny of D&D.
• Players can get good at math if they suck.

Cons:

• Loss of flavor for people who value it. Note that a PC can be assumed to be carrying different coins.
• Probably not compatible with VTT or digital applications.

Charisma Checks suck

 Dump Charisma checks!