Quite a few folks shoot trap, with a 28 gauge as they do 5 stand, and Sporting clays.
Quite a few places have "short courses" set up for .410 and 28gauge.
Set up Leagues for this too.
I would go try a bunch of different guns and see which one fits you best and you shoot best.
For those that do not know, many of these Short Courses and Special Leagues were set up by Seasoned Shotgunners.
This all came about when these folks that have fired
HUNDREDS of Thousands of shotshells and detached Retinas, neck, shoulder, injuries from shooting so much took its toll on the body.
Then folks that injuries from car wrecks, or whatever, surgeries and physically limited folks were invited into to these games for the smaller gauges.
28 gauge is not expensive to reload, really hard to put a value on being able to shoot again, when the Doc's said you might not ever walk again, or be able to shoot any kind of firearm again, or any number of experiences I am familar with.
Then again one of my old shooting pards ran a straight with Beretta 303 in 20 from back a few yards at trap
He also shot 98/100 using a 28 ga 870 from the 16 yard.
"Not the 28ga's fault, I just did not do my part".
Find a gun that fits, and have fun!