Option 1 (Formal & Poetic):
> Ας γεμίσει αγάπη, υγεία και ευτυχία. (As gemissei agapi, ygeia kai eftychia.)
This translates literally to "May it be filled with love, health, and happiness." It's a straightforward and elegant choice.
Option 2 (Slightly less formal):
> Να γεμίσει από αγάπη, υγεία και ευτυχία. (Na gemissei apo agapi, ygeia kai eftychia.)
This translates to "May it be filled *from* love, health, and happiness," subtly implying a source or origin for these blessings.
Option 3 (More emphasis on wishing well):
> Εύχομαι να γεμίσει αγάπη, υγεία και ευτυχία. (Euchomi na gemissei agapi, ygeia kai eftychia.)
This translates to "I wish that it be filled with love, health, and happiness," making the wish more explicit.
Option 4 (If "it" refers to a person's life):
> Να έχει αγάπη, υγεία και ευτυχία. (Na ehei agapi, ygeia kai eftychia.)
This translates to "May (he/she/they) have love, health, and happiness," which is a more natural way to phrase a blessing for a person's life.
The best option will depend on the specific situation and your desired level of formality. Option 1 or 4 are likely the most suitable for most situations.