Since I'm actually about to start playing it for the first time, figured I'd see if anyone has some helpful feedback/ideas for a subclass I've created -- The Rascal, which basically answers the question, "If Aladdin is a rogue, what does that make Abu?"

It's a fairly straightforward port of the Beastmaster ranger subclass, but with a roguish skill monkey (ahem) twist.

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While a Rascal has many skills and abilities of their own, they are best known for the partner in crime that always accompanies them. Whether it's the monkey with nimble fingers who is best friends with a street urchin, or the faithful dog who can sniff out the most valuable items to steal, a Rascal has an animal companion who is much more than just a pet.

Rascal's Companion

At 3rd level, you gain a beast companion that accompanies you on your adventures and is trained to assist you. Choose a beast that is no larger than Medium and that has a challenge rating of 1/4 or lower. Add your proficiency bonus to the beast’s AC, attack rolls, and damage rolls, as well as to any saving throws and skills it is proficient in. Its hit point maximum equals the hit point number in its stat block or four times your rogue level, whichever is higher. Like any creature, it can spend Hit Dice during a short rest to regain hit points.

The beast obeys your commands as best as it can, and understands any language you can speak including Thieves' Cant. It takes its turn on your initiative. On your turn, you can verbally command the beast where to move (no action required by you). You can use your action to verbally command it to take the Attack, Dash, Disengage, or Help action. If you don't issue a command, the beast takes the Dodge action.

If you are incapacitated or absent, the beast acts on its own, focusing on protecting you and itself. The beast never requires your command to use its reaction, such as when making an opportunity attack.

If the beast dies, you can obtain a new companion by spending eight hours bonding with a beast that isn’t hostile to you and that meets the requirements.

Companion's Edge

At 3rd level, you have trained your companion animal to assist you with certain tasks. As long as the beast is with you, you have expertise (doubling your proficiency bonus) on one of the following skills, chosen when you gain this feature: Deception, Intimidation, Performance, or Sleight of Hand. You also gain proficiency in Animal Handling if you don't already possess it.

Deeper Bond

At 9th level, your bond with your animal companion has deepened considerably. You may issue commands to your companion without speaking, using only a series of subtle gestures and changes in facial expression. In addition, you can understand its attempts to communicate with you, if the message or idea it is trying to convey can be reduced to a three-word phrase (i.e., 'Door is locked', or 'I swallow gem').

Your companion has also learned a thing or two from you. The beast now gains proficiency in the skill you chose with Companion's Edge and with use of thieves' tools, and adds your proficiency bonus to those checks. As a bonus action, you may order your companion to use these skills.

Exceptional Training

Beginning at 13th level, you can use a bonus action to command the beast to take the Attack, Dash, Disengage, or Help action on its turn.

In addition, the beast's attacks now count as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage.

Double Team

At 17th level, attacks made in conjunction with your animal companion become especially lethal. When the beast assists in creating the conditions for a Sneak Attack, such as by using the Help action or by being within 5 feet of a target, your Sneak Attack damage against that creature increases by 3d6.

I like it a lot. It seems slightly more potent than the beast master do to the out of combat stuff, so it isn’t weak. However, the second paragraph of the level nine feature allows you to take a bonus to allow your companion to ‘use the chosen skill’, which isn’t an action.

Quote from Dragonslayer9 >>

However, the second paragraph of the level nine feature allows you to take a bonus to allow your companion to ‘use the chosen skill’, which isn’t an action.

I included that because some of the options can have applications in combat, so it seemed to make sense to have an action economy cost attached, just as if you were telling your companion to Attack or Help. Obviously if you're not in combat, that wouldn't matter.