Garmin Swim 3 ???

Actually both look like touchscreen toys. Neither seems to be really suitable for in water use. Fortunately Garmin also realized that many people hate the touchscreen, and in serious sports watches they kept button operation as well. 

Finally Garmin 165 is here !
I think it is closest  to what we all need from Swim 3.
Amoled, large font option, SpO2,  
Open water and Pool modes, Drills and workouts support ...
And price is comparable to Swim 2
www.garmin.com/.../1055469

Yes, even version without music is $249  ...

Yes, all those you wrote are needed.  
I want to add some more
- Tide information, helps plan for openwater
- Bigger battery and solar charging, body may be bigger instead of thicker. 
- Editable activity screen, individual focuses different area, while activity, I want to chose which one on first screen, top middle or bottom.  To me maybe Time, Distance, Heart Rate. 

Just a warning, FR165 does NOT have all the features what Swim2 has.

See comparison, swimming functions

https://www.garmin.com/en-US/compare/?compareProduct=1055469&compareProduct=665374

Missing:

- pacing alerts

- pool swim workouts

- CSS

- external swimming HRM compatibility

My personal comments on the missing functionalities:

Most people who complain about Swim2 have problem because they use swim workouts - they still need triathlon watch

Pacing alert sounds a useful option, but I never used it.

I made CSS tests always manually, as I never trusted the workout function. Garmin does not use the potential of CSS beside of storing the data.

Swimming with external HRM felt always awkward for me, OHR is unreliable though

Side note:

It says that advanced workouts are supported, but swim workouts not! If someone buys FR165, needs to get confirmation from Garmin or seller

I am checking on whether I should replace my squeaky Swim2 with a FR165 and one of the things I love about Swim2 was the external HRM.  This is a real bummer if it cannot, but I checked and found a newer version of chest strap HRM called HRM-Pro Plus.  It'll have to do, if it comes to that :-\

The other thing is, HRM in water was useful in the earlier days for me but not so much now that I have done a few years of that (and limited usefulness for long distance swimming).

FR165 it is then!

I recently posted in the Accessories forum about the HRM Pro+ and whether it was suitable for lap swimming.  Consensus was that it worked in a pinch but tended to slip and move quite a bit... the HRM Swim was still my best bet.  So may want to keep that in mind 

The venu3 doesn't have structured swim workouts which is so silly because it would be so easy to include it they don't for some reason. 

I tried my HRM Pro and I found it slipped to much