yes is next major release not maintenance releases.
you can use pfsense using its built in functions without touching the command line, the only initial bit would be when booting up the first time and telling it which ports to use for lan.
Asuswrt is similar, it has command line but a gui frontend, you can use with just the UI only but of course UI only means you not utilising the full potential, but the UI has a lot of core functions in place.
PFsense is definitely UI focused, you can add plugins via the UI and those almost all have UI elements.
There is cli packages but none are required for core operation, they just useful for nix fluent users who want specific tools for advanced stuff.
If you leave the ssd misaligned and with trim disabled, the affects are lower performance (but the performance would still be fine for typical router use) and faster wear on the flash storage.
An example of what can only be done via cli is enabling checksum offloading on a per device basis, the UI lets you turn it on and off but the setting applies to all nic ports, whilst in the CLI it can be toggled per port. However for the majority of situations the UI on/off globally is enough.
I have applied various tweaks to loader.conf and sysctl.conf but this is from my knowledge of FreeBSD, some of these tweaks are configurable in the UI tho as well so can be done via point and click.
Ronski now pfsense is installed, another suggestion.
In the GUI you should find reference to powerd, you will want to enable that to allow the cpu to fluctuate its clock speed for better temps and power consumption, also select either adaptive or hiadaptive mode. hiadaptive is adaptive but will increase the clock speed with less load than adaptive and also take longer to reduce clock speed when idle. There is also options to enable advanced temp sensors so can monitor temp of each cpu core.
SUJ is soft updates journaling, soft updates itself is complex and not a great system, SUJ adds some journaling to the soft updates but its not the same as traditional journaling as seen in ext3/4 and gjournal, SUJ adds extra writes to the ssd, and the track record of SUJ is also not great in terms of filesystem stability. Its main purpose is to try and avoid long fsck after a improper shutdown, but fsck is very fast on ssd's anyway and not to mention the filesystem usage on a router will be very small so the benefits of skipping fsck is minimal.