- each website is handled by a module that does all the scraping, or uses the api if needed
- each module provides one or more capabilities, such as "list an account transactions" (typically for your bank or your mobile provider) or "receive and send messages" (such as HN or reddit or tinder)
- applications plug into those capabilities and give the user functionalities, regardless of the website. You can list the schedule for your bus just as well as the schedule for carpoolings.
One of the applications is actually a daemon with the capability to send and receive messages (with threading and all) and sends messages to the email adress of your choice; you can also configure it as an smtp mta, which means you can use any mail client and interact with all your discussion websites without ever opening the browser.
Obviously this is not a perfect solution for OP's problems, but it seems to me it's going in the right direction. Oh and it doesn't stop at websites; I use it for sending RSS feeds to my email in the background.