I've spent a lot of years hopping between a Dromader or a Thrush or an Air Tractor 502 or 802, and a Learjet, 747, etc, back and forth. The "ag stink" is real, but in today's market, largely superfluous. If you're multi current and instrument current, that's what the employer needs to know, and can you pass a checkride and a type rating? Once the foot is in the door, nobody will much care what you were doing before.
For a lot of years, the "airline stink" put a stigma around those with 121 time who tried to go somewhere else, and most of us are familiar with the 121 guys who wanted to fly ag or other such stuff. Nightmares. Almost as bad as military pilots trying to fly ag. Ugh. (then again, crawl out of an 802 and into a F-16...)
When I did my type in the 747, I'd just barely come out of an 802 a couple of weeks prior to ground school. In the sim when we did a V1 cut, I mashed that rudder and the airplane tried to roll over on me. The instructor his the freeze button and asked what the hell I was doing. It took a couple of tries to figure out that the rudder was several stories tall, and I didn't need to throw it around like a tailwheel airplane. For me, it was the transition back and forth a few times a year, low and slow to high and fast, that was exhausting. More so, the older I got. Dogs, tricks, and all.
Ag aviation (and fire, and other utility stuff) does carry the cowboy stigma, and it's viewed through the lens of ignorance by many, usually those who couldn't fly their way out of a wet paper bag. Many moons ago, a very condescending captain in the 747 remarked, when he learned of my ag background, "I guess you don't have any precision flying experience, then." I asked if formation flying under powerlines at gross weight in strong winds counted, and he said, "we don't do much flying under powerlines, here." Point taken, but his ignorance ran thick and heavy. Nice guy, but an idiot. Don't let those who don't understand where you've come from, stand in your way. Apply, interview, go to work, and ignore those who tell you that you can't. They're wrong.
You can upgrade with a regional, and you can upgrade with a legacy, if you're willing to travel and work out of places you don't want to move or live.
You might be happiest at an ACMI carrier doing freight or somewhere like Omni, doing passengers. Those kinds of outfits tend to have broad experience base among the crew who come from every walk of life from corporate to military to regional to utility to cargo, and the culture tends to be a bit more reflective of that, too. The flying tends to be interesting, the destinations varied, and in my opinion, the work rewarding. It's not ag, but then nothing is, and while staring out the window for ten hours on an oceanic trip isn't the epitome of excitement, after the third or fourth pass on a field, that becomes work, too. Different strokes. Give it a look, all the same. Apply. Interview. You can always say 'no.'