In all honesty, I find myself using grenade more often than invisible shot. Yes, I agree that invisible shot is the leveling skill; however, I believe that there is viability in getting 1 invisible shot and then going a support build. Sure that makes leveling harder but in the end, a 100% stun rate with flame thrower and grenade burn could potentially help out your training at various locations and decrease the potion usage. If you look at it, the majority of the 2nd class skills for pirates are support, invisible shot being the odd one out. I realize that ice spitter + flame thrower completely replace invisible shot. That's why I offered the support as a possibility. I would agree that blank shot should be replaced by grenade if you're interested in going that route, that's the build I did with my slinger immediately after bb because i was interested in trying out grenade.
Once again, I'd like to offer the support build possibility up for discussion.
I disagree here xD In lower populated worlds, jesters are a somewhat viable location. Since you're only able to mob 2-3 early on in your 3rd job, you can easily take a corner without complaint. Sure other monsters may be slower, but that's just part of the game. I remember wrs and how they used to be amazing exp, newts used to be good exp, 8x used to be good exp (although i never managed to get that high xD), but did people quit after that? No. Sure some did, but if you've found your calling as a gunslinger, you should have that 4th job in sight and be willing to grind to those levels (with breaks in between of course)
Thanks for catching that xD Meant to say first 2.