Hostas and Black-eyed Susans are unlikely bedfellows.  Hostas require shade and Susans prefer full sun.  At this time of the year, the Hostas look fried, not diseased  They are also hanging over a slab of very white cement that is radiating heat and cooking them more fully. The Susans generally do not look that good at the end of September.

Do some research over the winter and find plants that can handle more sun than Hostas and are also heat tolerant. Buy some books on perennials.  Decide when this bed needs to be its best.  With perennials, there will be some times they are up and sometimes, like now, that they are closing up shop for the winter.  Annuals will give you more flower power if that is what you are looking for. 

Since this bed is going to be what you like, it is going to be very difficult to decide what you will like or put up with.  You might have a groundcover like Vinca minor and areas of plantings of chosen annuals or perennials and the groundcover is common thread that ties the areas together.

Consider relocating plants that you do not want or giving them away.  Pulling them out sounds like the final solution and they are on their way to the compost pile.