Apart from playing more, there are ways to improve your practice by carefully picking maps to practice on.
The first step is to identify your weaknesses. Are you bad at jacks? Do you struggle with LNs? Do you feel like your speed is becoming a problem? etc.
Once you've identified where your weaknesses are, you can begin looking for maps that are good practice for those skills.
For example, one problem many people have is speed. There are 2 main things that can cause problems with speed. Bad technique, and difficulty reading. Yes, reading. Most people seem to think that either you can read a pattern, or you can't, but in reality, reading a pattern takes a certain amount of time. If that amount of time is just slightly too long, you will have difficulty hitting the pattern well, even if you can combo through it, you will find yourself either rushing it, or hitting late, or sometimes essentially mashing through it resulting in hits both early and late. The key to practice reading is to identify which kinds of patterns you struggle to read and trying to find maps that use those same kinds of patterns, but are just a bit faster than you're able to play well. Difficulty reading can also lead to bad technique. If you find your fingers tensing up too much when you play, that is bad technique and will slow you down, drain your stamina, and reduce your accuracy. The key to better technique is a bit more difficult to improve unless it's reading related. If it IS reading related, practicing reading harder maps will help. If it's not reading related, then you need to practice hitting the keys more lightly, reducing the amount of distance between your finger and the key, and potentially learning other techniques to play certain kinds of patterns (for example, wrist jacking, vibro, jumptrilling rolls that are fast and other pattern manipulation techniques).
Practicing LNs is more straightforward. Find lots of LN based maps, try to learn which LN patterns you struggle with more than others and incorporate more of those maps in your play sessions.
Another thing to consider is reading techniques themselves. For example, when I play jack heavy 4k maps, I tend to mentally separate the columns into which hand I use. So the left 2 columns and the right 2 columns are treated as mostly separate patterns. That way I can focus on what each hand is supposed to be doing separately. For LNs, I try to focus on the LNs more and worry less about the extra notes, since my brain already knows how to hit regular notes pretty well. For chordjack patterns, I focus on reading each chord separately, but on stream heavy maps I focus on reading the patterns more "vertically" by reading ahead more and looking at the overall pattern of the stream.
It can be difficult at first to begin identifying your weaknesses and figuring out the right way to practice them but if you figure out how to do it, you should be able to get much more efficient practice than just playing whatever you feel like without focusing on your weaknesses.