I'd like to play devils advocate here.
1. Cardio - it's a big part of why many people join a gym in the first place. Loads of students have problems with self motivation, and they join classes to help them stay motivates and in shape. In a perfect world I could wake up in the morning and hit the gym at 6 am and hit a killer work out, but left to my own devices, that tends to not happen. If an instructor puts a reasonable amount of cardio into a class, it's a gym, don't be lazy.
So What I hear from people is you should go do work out at a separate time from Jiu Jitsu? Who has time to do that? Most ppl don't have the luxury of doing yoga for flexibility, going to lift weights, doing cardio 3 times a week, doing crossfit for fast twitch, doing trx for slow twitch, doing wrestling for their takedowns, breakdancing for their balance and core, jazzercise for their overall jazziness and Pilates to meet women etc.
2. Instructor rolls with students. Now I get this, who doesn't like to roll with the coach right? However, if you have 20-30 students in a class, it's easy to get overlooked for years if the instructor rolls the whole time. This is not to say the coach should be texting hot galz or youtubing dancing cats the whole class either. I find I can help a lot more students if I'm mobile during the rolling. That way I can coach multiple students, protect from spazzes, keep an eye out for safety, get a better idea of my students strengths and weaknesses, stop white belts from heel hooking everybody etc. I really have no idea what's happening outside of my own space if i'm rolling the whole time.
There's no doubt on- on-one time is awesome, but not at the expense of the whole team. It can be frustrating to be overlooked or ignored by a coach. I love rolling with the students, but I find that it's not always the best strategy to foster the strongest environment of a team.
At the end of the day it's about progressing my students. If my team will progress better by rolling with the students more, then that's what I'll do. If I need to supervise the entire class because that's what gets the best results, then that's what we'll do.
3. Is a 420 friendly gym important? I would hope That any gym you'd choose would be friendly and non judgmental towards lifestyle. I mean I could see training with somebody like Cyborg, who hates weed people, being an issue, but I wouldn't let my enthusiasm towards the pot get in the way of training.
As a coach I'm not unfriendly towards weed, but I don't promote openly either, I guess it's a non factor for me. It does however offend certain people, so I tend to stay away from the subject in class. aside from jokes. Same as I stay away from religion or politics. I've come to realize not everybody in 10th Planet loves sex, drugs and rock and roll. I don't want to alienate a student who really wants to learn Jiu Jitsu because we have a difference of opinion off the mat.
***To answer my own question, if my gym blew up what would I look for. I'd look for an instructor that has right attitude. I want somebody who keeps me motivated to train. I'd look for an instructor who would be fun, someone who promotes a healthy learning environment, and somebody who is gonna help keep me in shape.