Hi... thank you for your great question!
I have a short answer and long answer. The short answer is Filler would prob work best if I had to choose one treatment.
I always talk to my patients about what they can afford and how full-out crazy do they want to attack the area that is bothering them. One vial if filler could probably soften these lines enough that you will be happy.
We used to just fill in these lines with filler.... and someone in their early 30s can probably still get away with this route and it may be the cheapest way to go. The correct way with filler however is to revolumize the cheeks with filler. Perhaps one whole vial on each side and that will lift the cheeks and those wrinkles/folds around the mouth will go away.
Also though.... I would say to be sure your skin is healthy and moisturized. Use a good product or get a good peel so that your skin has good moisture and elasticity. There is a aquagold and microbotox procedure that can really help with this area of the face.
Microbotox is injected superficial in the cheeks, not the muscles, so the pores tighten, and areas treated are smoother and the skin looks radiant. Aquagold is similiar but there are several product injected all at once with aquagold and not just botox.
Laser rejuvenation and peels can also improve skin by exfoliating and tightening the skin.
So if you have lots of money to spend or someone wants to spoil you, get several treatments and then you will just need maintenance every now and then.
Start with laser or a good peel. Then continue to improve the skin with a microbotox session. Then if you can add volume to your cheeks with a product like Restylane Lyft or Voluma.
If you live in the real world, and really don’t have the money right now then invest in a really good exfoliating product at home and moisturize every day. Wear sunblock and buy one vial of filler and have those lines filled in. Or ask your injector if one vial would be enough to add volume to your cheeks. Depending on where you live.... this alone will probably be 500-600 dollars. Could last you a year while you save up for the whole shebang.
Best of luck! I hope you are happy with whatever treatment you decided for on!