I don't think one is really better than the other. There are trade offs with either of them, it just depends on which you are more willing to do. Then it depends on what type of gecko you got as well.
Pros for general care of snakes:
Feeding only around every week. Poops once a week generally, so major cage cleaning can be done every few months, with spot cleaning in between. Can leave for a week or so without a sitter. Can be fairly pricey for the initial setup & the animal but normal upkeep isn't much.
Cons: Depending on the sources available to you, mice can be fairly expensive, up to $15 to $20 a month for one snake. (that's what it would cost using the pet store around here but isn't where I buy my mice) Some people are squeamish about feeding mice.
I have decided not to breed my corns for several reasons that may or may not apply to you.
The possibility of a 30 to 40 eggs clutch is a bit intimidating to me. (unlikely to get that many but possible & I like to be prepared for what could happen)
Would need individual cages with heat for all the hatchlings. They will all hatch at once. While there might not be a problem with any of them, it is possible to get a whole clutch full of non-feeders. And finally, around here I think the market for corns is saturated. I mainly wanted to breed for the experience of doing it & quite probably wouldn't have bred them more than once. So becoming FedEx certified to be able to ship snakes doesn't appeal to me for only one clutch.
Pros to Crested geckos: (since those are the only geckos I have experience with)
Don't generally need heat, room temp in most homes is great. Eats a powder that you just add water to. Doesn't need bugs if you don't want to feed them. If you buy the powder in bulk, you can get enough to last one gecko a year for about $11 to $15. Can be pricey for initial setup & the animal but normal upkeep is minimal.
Cons: Need to be fed every 2 days. Need to be misted about every day depending on the humidity where you live, could be more often or less. (I don't personally find this a hardship, takes about 15 min. to take care of my 4) Will need a sitter if you are going to be gone for longer than 3 days.
Breeding my cresteds appeals to because: They lay their eggs 2 at a time about every 25 to 40 days, 16 to 20 eggs in a season. That gives you time to build up to more & more hatchlings & making sure they are thriving. They can be housed together (have to watch out for bullying & separate if that is happening) but since they won't require supplemental heating, it is easier to house them, even if they are in individual cages.