Don't use an arpeggiator. It's fun at times, but the benefits of not usin one are even better. All depending on what arpeggiator you're actually using, but I'm sure it's not that sophisticated. With that bein said; practice, remake some, get off that grid, the velocity & panning aren't necessary, but they'll definetly set it off. Idk what you workin in, but what helps me is workin in doubletime, & I've recently started workin on quadruple time as well. You can do all the same things in normaltime, but it's just the ease of it. Ain't no advice gon help you more then the actual experience of puttin in that work. Take some of the ideas I've stated & even come up with your own.