I love the delicate nature of the tattoo, and the use of colour as opposed to black. the only think i would worry about is the colors bleeding in over time, like my mother's did, but i assume you know what you're doing.
thank you. if your mother's tattoo colors bled in over time it could indicate either that the artist penetrated too deeply into the sub-cutaneous layers (we call this a blow-out) or that she had already-damaged skin either from age or UV-light exposure or both. That makes skin highly susceptible to blow-outs or ink-bleeding. I've tattooed my mom's tan-damaged skin also and it doesn't work the same way as younger or undamaged skin.
Alternatively, the ink may fade over time even if it doesn't travel (bleed/spread) much. Fading is usually caused by a combination of your body's slow absorption of the ink and destructive UV-light exposure.