During either player's turn, when your opponent activates a Trap Card while you control a Plant-Type monster: You can send this card from your hand to the Graveyard; negate the activation, and if you do, destroy it.
Sergeant Electro need to be summoned. In some cases, you don't want wasting your normal summon just for that. Rose Archer in other hand could negate the opponent's trap card from hand. But, it all depend from your choices for making the best deck ever.
Used to be no better back row choice for aromages. But doesn't mesh well if you're trying to run the aromaseraphy and spell Absorbing life combo- spell Absorbing overrides rose archer's activation. Cosmic cyclone is a better option. Aromages can spare the l.p., and it's superb for getting geartown off the field safely. Can also he used anytime.
Black Rose is same as Daedalus, even it could be worse since Black Rose leave you without protection
It is a nice card, but I question whether it should be the best choice for protection against the opponent's backrow. Destroying traps is good, but more often than anything else, it is the endless econs that I run into. To run it, I would at least pair up rose archer with something else that can stop spells as well.