Alternatives

There is no such thing as a perfect layout, period. Every layout has its own pros and cons - Night among them. Thus, it's a good idea to take a look around and see if there're any alternatives that might suit you better.

I will provide my own opinions on each of the layouts - you can identify them by the italicized text. I will try my best to judge each layout objectively, but I am inherently biased - just keep that in mind.

The most popular modern thumb alpha keyboard layout, it is incredible in its stats and performance. It's essentially the Graphite or Gallium of thumb alpha layouts. The main drawback of Dusk is the sorting of the letters (the arragement) on the index. W being placed on the corner just does not make sense as it is rather frequent. Her reasoning was primarily that of the corner + homerow LSBs being more comfortable than center + homerow; I suspect this is due to her using a Piantor. In any case, ' being placed above L and M is also not ideal. I'll and I'm are some good examples that suffer from this. In any case, Dusk is an absolutely great layout, but I would personally swap around some keys.

Racket

A very good layout that favors heavier non-index usage, Racket is a partially inroll focused layout. It utilizes lighter indexs for heavier middle and ring fingers. I personally, accidentally, created and used a layout extremely similar to this called Stern (index keys swapped and V being in the position where F is) up to 160 WPM so I can confirm it certainly works. My only real complaints for this/these (Stern) layouts are that LHM can be a bit heavy movement-wise for some people. The frequency of LL exemplifies this and makes the middle finger jump around quite a bit. Nevertheless, it is usable and certainly competes stats-wise.

North

Another layout made by me, North is best described as a "balanced" layout. It is not as good as Night in terms of SFBs (nor Dusk, Racket, or any other thumb alpha layouts on the recommended list), but blows every other layout on this list in terms of SFSs. It trades off that SFB for more comfortable key positions (maintaining a low-use bottom row, frequent same-row bigrams, and symmetrical usage). The main downside of North is D_V and L_V which cause semi-frequent middle-curl scissors.

As a side note, you can trade SFSs for a bit better SFBs by swapping ' and ;, but it is still not as good as Night or Dusk.

Bunya

Bunya, another layout by the creator of Racket, is a similar layout to North (developed independently, but prior to North). The major advantge of Bunya over North (and all layouts so far mentioned) is its use of high usage letters on both indexs. This, along with other letter positionings, makes this an overall very comfortable layout to use. Think of this as North, but with more comfort and slightly less efficiency. Again, similar to North, the primary downside is the V curl scissors and worse SFBs compared to Night and Dusk.

A side note for this as well, I would personally swap W and P for the same reason as Dusk.

Not Recommended

These are alternatives that I would not recommend. The majority of them have significantly worse stats (to the point of being redundant compared to non-thumb layouts) but may provide useful historical context.

Aptmak

Created around 2022, Aptmak is likely the most used thumb alpha layout. It shares a very similar design to RSTHD (see below) but reduces SFSs and reorders some keys. Compared to the likes of modern thumb alpha layouts (Yes, 2022 is considered old already), it suffers from much worse stats in both SFBs and SFSs - even the likes of non-thumb layouts have beaten it. However, it does have very respectable inrolls, but there are better alternatives for that as well. I personally would not recommend this.

RSTHD

Created around 2016, it was quite ahead of its time. However, being very similar to that of Aptmak, nowadays, it is not very competitive. Compared to Aptmak, while it is not flat worse, it is very nearly so. Thus, I would also not recommend this.

Maltron

One of the oldest layouts as a whole, it is remarkable how good it is - especially considering its inception around 1976-1977 (See 7. Maltron Operation). It is honestly incredible how good it performs stats-wise - with SFBS and SFSs ironically being better than that of RSTHD and Aptmak. Unfortunately, again, modern thumb layouts have surpassed it and thus is no longer recommended - also, it has rather high redirects.