Mapping takes so much time and effort and if you start making a map with the intention of it being bad and then 180 at the end cause you want people to play it, the amount of time and work it takes to go back and fix everything to bring it to a playable state takes forever.
When you decided to make a terrible map you should've stuck with that instead of trying to fix it to make it playable. I would take all the practice and skills you got and make a good map that you're happy with and release that one instead.
In the future before you start making a map I would decide on why you're making it, is your intention for it be publicly played, or is it just a throwaway for practice and testing etc.
If you really want this map to be on public servers I would go back and fix everything even though it will probably take a long time. My suggestion however is to just scrap this map, start over and make something you're going to be happy with.
PS.
When I was making my first map even though it wasn't the greatest I was getting super impatient because I was so excited for people to play it that I ended up rushing it and in the end wasn't completely satisfied with the map. (Thanks to sneak though he basically forced me to polish up the map as best as I could before release ?)