Just a couple of observations looking at your stage. Your guitarist has a DSL, I'm assuming 40 watts tube. That amp can get pretty loud. If your sub is cutoff at 80mhz, or even 120, there's a lot of critical low mids that those 2 flyers you have may not be able to do justice to. It's a big misconception that FOH support for bass is only in the <100mhz range. I find the low mids and high mids can be even more important and hard to be supported properly if the FOH speakers aren't up to it or if the bass is routed to just the sub. But, let's say for a minute that the PA was 'adequate' (even though it seems the tops are a bit small for a mid-to-loud outside gig), I personally would want a 2nd bass cab. Like Agedhorse was alluding to, a tilted cab might put more sound toward your ears. But, for outdoors, I like a stack so the lifted cab is closer to my ears and the amp has the ability to push more air. If I were eye-balling that setup, I'd have probably thrown 4 flyers instead of 2 (helps that I carry 4 in my trailer), probably would go 2 subs, and would have have had a 2nd bass cab. There's no right or wrong with any of this, I'm just saying that's how I would have spec'd out what I see in the picture for a mid-loud rock band outdoors.
