I do think its well rounded but because of that it doesnt exactly shine too much in any particular task.
Aoe, you have broom trap, barrage+ feint, cannoneer, and detonation. Detonation from sapper is a very underrater skill, if you have a bow and maxxed attribute vs flying you do 350% damage with it. You can explode almost everything, heal tiles, ice walls not only traps. At level 90 I was already doing 7k crits per tile with it, and I had it on level 1 with 0 in attributes.
Capturing traps is a great mechanic aswell, which allows you to get your party’s traps on world bosses and boosting your own damage. Not sure if it works for guildies who arent in your party, they are by definition your allies so it might. Works for magic circles too but I do not have a full applicable list for you.
World boss wise it does good but as always, everyone is outshined by fletcher 3. Its how it is. You have good sustain with flare shot and broom trap, chrono can increase your damage by a lot by resetting your cooldowns but that works for just about any class.
Et I have no experience with, but I dont see why not. You have plenty of utilities, aoe damage ( sustained through sapper and burst through cannonner ), broom trap damage can be boosted very easily to some crazy values. Lethargy is +100%, rodelero can make it + 300% if memory serves or +200%.
Pvp wise, scout allows you good positioning and damage invulnerability through barrel, sapper can help you get rid of those pesky spells, good burst damage with both feint+ barrage and cannoneer, while flare can force people to run out of a safety zone at a distance too.