Great idea Edwin.
As for a theme, my vote is world peace. That covers just about everything if you consider that inner peace is the best, most true source of the outer peace that we'd all like to see in everyone and every situation.
If we are developing greater love, compassion, and inner peace, we can embrace the world and all beings with those vibrations
If we think that we gain merit through our good actions which can include meditation and helping others, we can also share that merit with all beings with the wish that they too grow towards a life of good.
One powerful Sanskrit prayer is
May all beings move from
untruth to truth
darkness to light,
death to immortality (meaning enlightenment).
Om shanti, shanti, shanti (peace)
But I think it's not so complicated in practice. We can just share our love with everyone, including our planet, Gaia.
So fellow meditators, in that spirit, I send my love to all of you
Bhavya