Over the past twenty-plus years, we've been in many of the rooms at SCC; some have views, some are upstairs, some are closer to the dive shop, some have double beds, some have kings. All of the rooms have tile floors, a/c, fans, balconies, free wi-fi, no TVs, and ambience. I would be delighted to be in any of them. Some of the rooms, like 71, are huge and typically reserved for group leaders or valued, repeat visitors. Given the dynamics of room assignments, you are unlikely to get a specific room. You can ask, but the staff cannot accommodate everyone; otherwise, we would all be in 71...with Betty!
The lockers are large enough for two sets of gear. The hotel is secure, theft is not a concern.
Dive guides? Love them all. Some are better at finding smaller critters than others. Most of the DMs have been at SCC for many, many years; there isn't much turnover. If you want to see something, tell the DM. If you want to dive a particular site, tell the DM. They can't always deliver, but they will do their best to show you a good time u/w.