Summertime Saga has no reason to update at a reasonable pace. In fact, it's in it's best interest to draw it out as LONG as possible. Until you guys stop giving Developers on Patreon 100,000 per month when they're releasing next to nothing each month, they will continue to do so.
This is just like Microtransactions. You guys complain about them, but then buy them. And this is the problem. You need to think better with your wallets.
If everyone stopped giving Summertime Saga money, I bet you a HUGE chunk of game would magically release to get patreons back.
Look, I think the Devs of Summertime Saga, the writers, and the artists have all done an amazing job. But you're talking about a 2D game. With as much as they're getting paid, a team could have finished that game in a month. Granted, they're probably using one artist, so there may be a bottleneck there. But there's no reason they can't hire another artist or three to copy the original artists style and make more content. So I just don't buy any excuses. They're slowly releasing to keep their patreon money coming.