If this is your first casting reel then I would suggest you get better at using it. Chucking a square bill a mile should be the least of your concerns. Understand the entire reel cast control knobs, breaks, free spool, etc like the other OP said accuracy>distance especially with a square bill and targeting cover. You don't need to upgrade bearings because I have three curado I's all with stock bearings my actual square bill rod is on a jackall poison adrena 6'6" medium and I can bomb an LC 1.5 .... The rod your using has a lot to do with casting distance and the specific rod your using is so so and pretty tip heavy which may have something to do with your end result as it's a medium heavy rated for 3/8-1oz and you stated your primarily casting 5/16-3/8
Learn your reel, flush those bearings, try a different rod possibly and see if your results are similar. Tight lines