>>47700658Aside from gift opening you can also take advantage of exp boost events. Save up easy shitmons to evolve during 2x evolution bonus spotlights, drop lucky eggs and make as many excellent throws as you can whenever there's a catch exp bonus happening, etc (I was getting 10k exp every excellent throw during cave hour on Go Fest day 1 because they bumped the bonus for great/excellent throws to x5, which I boosted with a lucky egg both times).
I've only been using free lucky eggs too and i'm just about to hit level 37 after just over 2 months of playing.