Much better UI/UX (in terms of looks and ease to navigate)
The app is feels much faster than Bitwarden’s, maybe its not objectively, but it feels lightyears ahead in terms of >speed
Possibility for separate email and username fields
more seamless integration with simplelogin aliases than what Bitwarden has
TOTP is available in the free version
Bitwarden is currently working on redesigning their apps, which will also include new native mobile apps that will fix the current speed issues. You can already test them if you are interested.
Even if Bitwarden doesn’t have as straightforward implementation regarding the separate email and username fields, you can easily use custom fields to solve this issue. As you also noted, Bitwarden will also autofill these.
Even though Proton’s SimpleLogin implementation is more simple and likely easier to use compared to Bitwarden, it also poses a serious lock-in issue with Proton Pass. If you ever decide to downgrade to a free plan, Proton will disable all your aliases that go beyond the max limit (10) in the free plan. This is a big contrast to even SimpleLogin that will keep all of your aliases operational even if you downgrade to the free plan. I would also take Bitwarden’s alias implementation over Proton Pass because they support multiple different aliasing providers compared to just SimpleLogin. In the past I have had issues registering a SimpleLogin alias for some sites, so all I needed to do was to change to DuckDuckGo that Bitwarden also supports and the site accepted that one. This is also a feature I doubt Proton would never implement because they own SimpleLogin.
Proton’s free version only supports three TOTP logins, so not very usable, and Bitwarden’s Premium plan is only $10 per year, so not a big deal to upgrade to that if you need this feature.
Bitwarden is currently working on redesigning their apps, which will also include new native mobile apps that will fix the current speed issues. You can already test them if you are interested.
Even if Bitwarden doesn’t have as straightforward implementation regarding the separate email and username fields, you can easily use custom fields to solve this issue. As you also noted, Bitwarden will also autofill these.
Even though Proton’s SimpleLogin implementation is more simple and likely easier to use compared to Bitwarden, it also poses a serious lock-in issue with Proton Pass. If you ever decide to downgrade to a free plan, Proton will disable all your aliases that go beyond the max limit (10) in the free plan. This is a big contrast to even SimpleLogin that will keep all of your aliases operational even if you downgrade to the free plan. I would also take Bitwarden’s alias implementation over Proton Pass because they support multiple different aliasing providers compared to just SimpleLogin. In the past I have had issues registering a SimpleLogin alias for some sites, so all I needed to do was to change to DuckDuckGo that Bitwarden also supports and the site accepted that one. This is also a feature I doubt Proton would never implement because they own SimpleLogin.
Proton’s free version only supports three TOTP logins, so not very usable, and Bitwarden’s Premium plan is only $10 per year, so not a big deal to upgrade to that if you need this feature.