I'm going through something similar after falling out with Bkool. I've been on there for years, and it was great at first, but for months now I just can't get it to work consistently. Getting my original Bkool trainer to pair had become hit and miss. When it broke (old and much used, I'm not complaining) I replaced it with a CycleOps Magnus, and I've only managed to pair it once. The videos often freeze for most of the ride. The 3D rides seem to work well, but the graphics aren't great. I've decided that I waste far too much time trying to overcome difficulties that shouldn't exist in the first place. When my subscription ends, I wont be renewing. Having said all that, lots of other people seem happy with it. Bkool seems to work better with some brands of trainer than others. Do some research on how the Kickr Snap performs on it before making a decision.
My search for alternatives has covered many of the options you mention.
Zwift - I've had a free trial. No video rides, so I didn't think I'd like it, but I did. A lot. So much so that I found myself doing much longer rides than usual. That must be a good sign. They announced a huge price rise a few days ago.
@CXRAndy has quoted the new price in his post.
Tacx - not tried it. It's "bluetooth only" on a laptop, and I don't want to use bluetooth so it never made the start line.
Sufferfest - too much emphasis on short, hard workouts. That's useful for training, but no good for my type of general riding. Also, the "free trial" requires you to give them your credit card data, which they promise not to use if you cancel at the end of the trial. I don't like companies that do things like that. Other apps offer a genuinely free week or two, so why can't Sufferfest. Another one that didn't get to the start line.
Trainer Road - like Sufferfest, it concentrates on hard workouts. It also doesn't offer any kind of free trial, but promises a refund if you cancel your subscription within 30 days. Another trick I don't approve of. Not for me.
Kinetic Fit - seems to be iOS or Android only, and only uses bluetooth connections. No good for me - I want Windows and Ant+.
BigRingVR - as mentioned by others, it has good videos and works well. The majority of rides are steep, so I wouldn't want to rely it for all my indoor work. As it expands the ride base it may well become suitable for me. As it is right now, it won't do on it's own. While it's in free beta-testing it would be silly not to try it.
Lastly, an app nobody else has mentioned.
Rouvy - I found this via
DCRainmaker's review (last year's, but the most recent I could find). It's a rebadged version of the old Virtual Training app by CycleOps/Saris. I'm currently having a free 14 day trial. Lots of videos from all over the world. It also has structured workouts, but again they are too short and too hard for me. The equipment pairs easily, the videos work well. It's like Bkool used to be when it worked properly, and I like it. There are four pricing options: 1 month standard is $8. 1 month Premium (has a few more options, including more videos) is $12. 6 months Premium is $66. 12 months Premium is $120.
My current thoughts are to sign up with Zwift and Rouvy. I had hoped that one app would do all that I wanted, but I'm pretty specific about what I want or don't want (as you may have noticed

) and there's nothing out there that ticks all the boxes. It will be more expensive than I'd like, but at least my trial on Zwift qualifies me for the pre-increase subscription price.