good luck 🙏👍. Where I live (close to a VFS Global office) I see these companies come and go rather quickly. I think the clue is to find an established agent (you can trust), and one that have both Thai and non-Thai employees so they can handle the communication and understand both sides of the process well.
One recommendation I would make is to make sure the Visa agent speaks good English as well as has good experience with Thai visa requirements. I have visited several apparently serious Visa agents in Bangkok (to make copies and take passport photos) and overheard their attempts to help foreigners. It's beyond me how some of them are able to do that successfully, hardly speaking any English. Personally (as a Norwegian), I used a Norwegian agent for both 3 months visa, retirement visa and local marriage and that worked very well with no problems. It was
Great hotel with a great view (particularly the B-building) is Shama Lakeview - close to Asoke BTS on Sukhumvit. Get a corner room above 20th floor if you can 👍