Good idea! The stock BB tail lights (stacked one above the other) aren't the most eye catching design - I rode with a group of BB's for many years and noticed BB's did not have brilliant contrast for brake & tail lights.......so I fitted an extra accessory LED brake lamp to my BB, just to add a bit of extra oomph and the appearance of an extra light coming on above the stock combined brake/tail lamp.
I think you may need to check local laws/regs about flashing lamps..... they may contravene some DOT rules, if that is an issue, and in particular here in Australia, may infuriate following aggro judgemental idiot drivers if they nanny flash too often, or are painfully bright.
I like the idea of attention grabbing tail and brake lumens and a few quick flashes to wake up following drivers can't hurt in heavy traffic...... being careful not to over do it (eg false alerting) and send them back to dream land.
I am reminded of being stuck behind a Mercedes Benz sedan one evening, with brake lights so bright they made me feel sick and I had to shade my eyes while stuck behind them at traffic lights..... that was really awful......... but thankfully I've not had the displeasure of excessively bright non DOT approved brake lights since then..... maybe someone politely told them to turn their fog lights off for fine night driving?
It's a delicate balance for sure
