I love playing off the bottom. Guard and half guard are def where I put most of my focus. When it comes to guard, my favorite combinations are setting up the guillotine off of a kumura attempt. There are also great transitions to 1.5, which open up the omoplata, kimura once again, triangle, and a foot lock if they attempt to roll out of omoplata. So much fun learning all the different ways to fight off your back.
Hope you are enjoying your training!
I am still a bit too early in my journey to really say where my strong positions are but I have learned a lot the last 2 weeks and I really like half guard now but also feel way more confident in being in someones half guard.
I enjoy my training a lot so far :-)