5 WK lessons a day is a little on the slower end, but seeing as you’re pairing it with learning vocab from Genki and are doing other things alongside WK, I wouldn’t worry too much! The main thing is finding a pace that you can fit into your schedule and keep up with every day, and depending on the other things you have going on in your life, you might have more or less time that you’re able to devote to SRS, in comparison with other people.
I will say that from my own experience, I’ve found that I’m now able to handle learning more words each day than I could when I just started. Once I really committed to doing WK, I started doing just 10 WK items every day (with no other SRS except for KaniWani), and then after I did a few levels like that, I picked up Minna no Nihongo and started SRS-ing the textbook vocab. For several months, I learned 3 kanji and 9 vocab a day from WK, and then I’d learn 30-50 additional vocab from MNN every two weeks on top of that (though, granted, many of those vocab were repeats from WK).
Then this year, I started actually mining vocab from my immersion reading, so my daily time on Anki has more than doubled, and I often learn about 19 words a day plus 3 kanji across both platforms. It was hard adjusting at first, but after I got used to it, it doesn’t feel so bad.
There’s absolutely no way I could have started out with doing that much, though! It just gets easier to learn kanji the more you learn, and it gets easier to learn vocab the more kanji you learn, and just the more Japanese you know. I’d pay attention to your own energy levels and see how things are going, and adjust your SRS load up or down as needed.
I do think it’s more dangerous to overload yourself and burn out than it is to go slow, so I recommend aiming for a daily lesson/review count that you’re able to keep up with even on your worst days rather than what you can do on an ideal day. If that’s lower than the kinds of numbers some other people are doing, that’s okay! I’m a fan of the Let’s Durtle the Scenic Route thread because of the focus on going at your own pace.
Becoming proficient in Japanese is a marathon, not a sprint, so even if you go at a fast pace, it will still take you years to learn the language. That’s why I think it’s best to focus most on what you’re able to do each day and let that decide your pace. Consistency over a long period of time pays off. If you can spend more time on it each day, that’ll help you progress faster, but if you set unsustainable goals, you likely won’t be able to keep doing it for as long as it takes to actually learn the language, so I think it’s really important to find that sweet spot where you’re putting as much time as you can into it without burning yourself out. The only person who can judge that is you!
I will say, at a rate of 5 lessons a day, completing WK will take you 4-5 years, which is on the slower end (I think 2-3 is closer to the average for people who reach level 60). If you’re fine with this pace and you’re supplementing with additional vocab/grammar study, then there’s nothing wrong with it! But just make sure you keep your expectations realistic for how long to expect WK being part of your life.