This manga could've just as easily been an artbook and it would be just as good or better. I believe that before adequately judging the work you should identify what it's trying to achieve and then conclude whether it succeeds but there's also something to be said about how valuable the goal is to begin with.

In case of Olimpos, author's goal (judging from afterwords) was to just draw a bunch of cute boys in elaborate outfits. The goal is clearly achieved as one again stated by author themselves but is there anything else of interest to the manga? Not really, the story is completely pointless and ties to mythology are even less than superficial. The only reason you might want to check this out is an elaborate bishounen art style. The illustrations really are gorgeous but personally I grew tired of seeing same few characters in same outfits and same poses for hundreds of pages. Even nice looking drawings don't excuse for lack of variety and noticeable lack of backgrounds. The only place the viewer properly gets a feel for is the miniature garden we spend a lot of time in. This is a bit of a shame cause given the characters there was opportunity to show off a lot more.

In the end, it's a pretty inoffensive quick read with a skippable story and some nice art, if that sounds like your thing then give it a try.