Azores in early November + São Miguel base

Go with the plan for a longer 9 night stay. As you already understand, the weather there is unpredictable all year long. I once had very rainy, windy, and cold weather for two weeks straight in the month of August. Go figure!

With nine nights, you can split your lodgings definitely between two locations, and even pick a third. I always encourage travelers to the Azores to think about their evenings and the ability to enjoy nighttime walks, with the availability of restaurants. Furnas lake sounds nice, but is quite isolated and not a great long term location. This is not a good base for any stay on the island if you plan on exploring.

The island is very big, and there are literally thousands of interesting spots to visit. Driving times will be longer than you think. For me, and thinking of your time frame and how and where you will explore, I would choose 3 nights in Ponta Delgada, 2-3 nights in Furnas village or Povoacao, and the rest in the Ribeira Grande area.

If you have not read the post at the top of this Portugal forum titled "Azores Islands Travel Advice", I encourage you to do so. There is a link embedded in the post (written by the webmaster) directing you to my Azores Travel Guidebook. The first 52 pages are absolutely free to read. Probably any question you can think of for visiting these truly enchanting islands will be answered in those pages. Then you can peruse all the driving and walking day trips I designed for Sao Miguel and all the other eight islands.

If you choose to purchase my digital book, you will have all the detailed information for Sao Miguel. Now you can fine-tune your days and nights as well as your accommodation locations according to where you will visit.

I am always available for questions through private message.

Thank you for the tips! I'll definitely look into a second location then (3 might be pushing it vs. my travel style).
Quick question on rental cars: there are many local companies, do you know of any "bad apples" to avoid? Ilha Verde reviews are mixed, but I'm not seeing obvious red flags for others.
Thanks!

Just about all the companies come with mixed reviews. Even with the biggest company, Ilha Verde, I once had an issue when returning a car that the attendant said had dent damage that was new. I pointed out that it was marked on the paper when I picked it up. However, he said the dent on the door was about an inch away from what was marked (I am not kidding) on the paper. I showed him the video when the I picked up the car. Only when I showed the manager inside the video and the paper where the damage was indicated was when I was believed.

I don’t 100% trust any car rental agency in the Azores, except our cousin’s in Santa Maria. I take pictures and a video of the exterior, glass, roof, as much of the undercarriage as possible, and interior before leaving the parking lot.

Read the fine print of your reservation, hours of operation, location of pickup and drop-off, and then read the reviews with a grain a salt. Adding a zero deductible insurance plan should alleviate any worries and concerns.

We spent 10 nights in Sao Miguel last September, five in Furnas and five in Ponta Delgada. Furnas is small but has some beautiful sights and also easy access to other sights on that side of the island. Ponta Delgada is a city also with beautiful sights and easy access to the other sights on that side of the island. We were able to enjoy both sides of the island without backtracking too much. This might be a better plan than all of your nights on Furnas Lake where you might have to drive to every sight except the lake.

Also, we did get 100% coverage on our rental car so we would have no worries when we returned it. Although we didn’t have any damage, it was worth the extra money for the sake of a worry free return.