I like how easy Shiori is to install and the UI is much more responsive than Wallabag (could be a config/install issue) but it does have some annoyances too:

• No mobile app (I think there is an abandoned third party client though)
• Session expires frequently in the Firefox extension, requiring frequently going into extension settings
• No koreader support for e-readers etc

But it is actively developed and it's the most promising alternative to Wallabag in my view.