Re: light a candle in memory of victims or Ruju’ ilal-Allah ?
I think societies evolve over the period of time. Now people wear pants shirts and western clothes across the county, but I remember till 1990s in our hometown, one of our teacher used to wear jeans and children in every street hooted him (including us from windows of our home). When we started wearing same, our elders reminded us about that hooting.
So people do adapt dresses, lifestyles form other cultures and as far as it is not termed as religious customs, I don’t see any problem in it. But if someone come and say that you need to wear long jubbas (as some wannabes wear in Pakistan) as its the attire Prophet (SAW) worn during his life and its the Islamic dress code, then I see a problem in it.
I again repeat what matters is dua for the victims. If someone does that by sitting at home or does it around a candle vigil or does it in between one minute silence or after reciting some surahs from Quran, its all good. You and me may prefer last option, others may not find that tofeeq and opt for other options.