Honoring deceased Mother - Tacky?

My mother passed away a few years ago and I want to honor her at our wedding. My first idea was to have her sister light a candle at the ceremony, but I don't want her crying and making me upset.

My father is dating someone and she will be coming to the wedding. I was thinking of putting a flower on the chair next to my Dad, but his girlfriend will be sitting next to him on the other side. Is this tacky? What else could I do? I'm not having programs, there is no special song she liked and there are no readings at the ceremony.

There are so many etiquette rules, I hate it. I'm just doing what I want, even though I hear it from my family members. Since my fiance and I are paying for the entire thing, they have no say. That's my opinion.

Brenda, my mom died too and I've been struggling with this as well. I'm having a Catholic Mass and have worked into the Ceremony language a blessing for the friends and family of "Bride & Groom" who have passed.....

In addition to my mom, his brother died a few years back....so it addresses the concern w/o making anyone feel uncomfortable.

As a side note - and this was my dad's idea - our father/daughter dance will be to the song my parents danced to on their wedding day. The only people who will know is us - but that's all that really matters anyway.....