Robaux also has the SWT16+ in addition to the LL8. If you want something comparable to the Tiptop Circadian Rhythms, this might be a better choice. The price of the SWT16+ is between an LL8 and the Circadian Rhythms, but is also available as a DIY kit if you're into that. If you want something where you don't create rhythms per step but more generating it by knobs, you can look into something like the vmpe.de Euclidean Circles V2 (has six channels) or something like Mutable Instruments Grids, which has three channels + three accent channels of 25 mappable pre-programmed drum sequences)
Good to keep in mind while browsing for trigger / drum sequencers is what type of workflow you want. The SWT16+ and also other sequencers like the Erica Synths Drum Sequencer have a different project setup than the Circadian Rhythms (disclaimer: I don't have either of these but am looking for a drum sequencer as well so I've read up on their workflow).
In the Circadian Rhythms you have 8 outputs, called channels here. All 8 channels are bundled together in a preset and you can have multiple presets, which are then sorted into groups.
What's interesting about the CR is that all channels in a preset have a fixed length of 8 steps and you "extend" those 8 steps by looping a selection of presets. So let's say you want a 16-step rhythm, you can achieve this by looping two presets (can be any of the eight presets in a group). The looping multiple presets means that you can experiment more with combining different rhythms that you've made, as opposed to the more linear classic TR style approach. Also the interface of the CR is different, depending of the amount of presets you loop you can edit the triggers of multiple channels at the same time.
The Robaux LL8, SWT16+ and others like the Erica Synths Drum Sequencer have a more "traditional" TR-style approach. Channels are bundled into presets (similar to Circadian Rhythms' presets) and then divided in projects. However in these type of sequencers you can most of the time edit the default sequence length per channel, which is probably 16 steps. Depending on the module you can select less than 16 steps (which can create polymeters) but sometimes also extend the sequence length to 32 or even 64 steps.
Euclidean Circles is more based the number of filled steps divided by the number of steps, however it also has a step edit mode per channel (with a max length of 16 steps). Mutable Instruments Grids is its entire own thing, you can find lots of explanations online on how it works but it might be worth to take a look.
On the ModularGrid modules page you can filter on drum sequencer with a maximum width. Set function selection to "drum" and second function to "sequencer", punch in the max with in HP and have a look. Of course you will find some other modules as well (like drum voices or melodic sequencers) but it should give you an idea of what's out there.
Oh and one more thing; if you look outside of eurorack, there are plenty of sequencers that are eurorack compatible, have loads of features and are on average far cheaper than their eurorack-sized competition. For example the Arturia Beatstep Pro and the Korg SQ-64 just to name a few. Compared to something like the Tiptop Circadian Rhythms, the Beatstep Pro is half the price and fully eurorack compatible.