If you don't have one, maybe a wireless unit?
This depends... Wireless is an
awesome quality of life upgrade for shows, but only if you avoid the 2.4GHz units. A $200 wireless might be great for home use, but if you're out there gigging, that same $200 wireless will struggle to hold signal in a packed gig. That 2.4GHz range competes with wifi and everyone on their cell phones, weddings and corporate events are particularly troublesome. I have a Line 6 G10 that's collecting dust because I couldn't get five feet from my amp without signal dropout. Kind of defeats the purpose of a wireless unit.

I tried a few units and finally upgraded to a Sennheiser EW-D, and am SO much happier.
If your gigging: I lightened the load with one of the Roadrunner soft "hard" cases. Much lighter carrying around basses. Get one for two basses to gig with. Had mine for a really long time.
Big +1 to a double bag. I got an iGig double when I first started gigging, and it's still been probably the best "convenience" purchase I've made. Always bring two basses to a gig. I'm finally considering replacing it after 15 years of solid use. I wish iGig was still around, because I've never seen another bag with as much storage... I can fit an amp, cables, and more in the front pocket.
If you are giggin' with a cab a folding hand cart.
Another +1 here. I've tried the Magna Cart and they're certainly handy, but I wanted something a little bigger with a little more stability... I've been using a
Rock-N-Roller Cart for years. Two bass cabs, pedalboard, gear bag, show clothes, sometimes small stage lights, occasional odds 'n ends... all in one trip.
A tablet for charts - if you're into that sort of thing.
Yet another +1. If you're in a gig that uses charts, an iPad with ForScore was a total game changer. All charts for everything in once place, complete with full annotation options. I still remember a particular three-gig day from several years ago... two different musicals and an evening gig with my main band at the time... I would have had a stack of binders for paper charts.
As a bonus here, if your pedalboard is set up with MIDI, you can also use an iPad to control it.


(MIDIPad for controlling, or you can program ForScore to send commands automatically.)
5sg.