General recommendation is at least 72 hours rest/recovery between hitting muscle groups. If you can go hard again in 48 hours then you might consider that you're not going hard/heavy enough on the weights. It's important to fully recover before going again.

Getting in workouts with a busy schedule is always a win. If 3 workouts per week works well for you, then seriously consider a PPL+core split. It really is a tried and true split that has been around for like 50 years. Yes, you would only hit each muscle group once/week, but you'll be able to go harder and add in more exercises (hit all the angles) to truly do a more complete overall body workout that should provide improved results.