Yeah, the first couple levels are slow, as countless threads, FAQs, and WaniKani emails will attest to, but in a couple weeks there’ll be enough to take over an hour a day, and that should be more than enough.
I recommend using bunpro.jp at the same time. They don’t limit the number of lessons you can do, so you can fill up any spare time learning there, and the grammar lessons have naturally taught me a lot of kanji and vocab that I haven’t yet encountered on WK.
Tae Kim’s grammar guide dovetails really nicely with BunPro, since BunPro’s lessons can be too brief. But they link outside sources, so you can always flesh out your understanding that way. I’ve just found Tae Kim to be the most thorough grammar textbook.
I’m not affiliated in any way with these sites, I just really like them. I always have those three tabs open on my computer. Oh, and a fourth tab for jisho.org, an online English-Japanese dictionary. Hope some of this helps as you start/continue your language journey! And hopefully those other sites give you a way to fill your time until WK heats up!