Storage Space Great Box?

You'll receive a bunch of OPINIONS so here's mine: Lucky eggs aren't worth the coins in any scenario. Leveling up comes naturally with normal play and unless you have some weird need to level up faster, at this moment it's pointless to focus on boxes just because of the lucky eggs they contain.

Having said that, the box's contents don't seem too bad but I will always recommend prioritizing storage and bag space over anything else until they are maxed. They are the only permanent investments that have an actual impact on gameplay over the long term.

I would spend them on storage.

Directly from the legacy box analysis on this website:
"Valuing only Premium Raid Passes and Incubators at full price, this box provides a 44.29% discount. This discount beats all previous Legacy Special Boxes and is rivaled only by this event’s Ultra Box, though the Ultra Box offers upgrades on the other items; Lure Modules into Incense and Lucky Eggs into Star Piece.

Noticeably, this box offers a higher density of Premium Raid Passes than this event’s Ultra Box. At 780 coins, it is more efficient to buy this box than Raid Passes, even if interested in no other items, offering a 2.5% discount on Raid Passes only.

While the Ultra Box is still a better deal overall, this box is still a great pick up. Valuing Incubators at 130 or less each (and other items at 0, Raid Passes at 100) actually makes this a better deal than the Ultra Box. That said, placing almost any value on Starpiece swings this back in the Ultra Box's favor. Trainers focusing solely on raiding or unable to afford the Ultra Box should still find this box worth picking up."

This box provides the largest discount that has EVER been offered on the combination of raid passes and incubators - the two highest quality consumable items in the game.

You can buy extra bag space at any time. You can buy this box only during this window.

The boxes have been getting better, so perhaps a better box will come around. Possibly not though. It's your choice. I ultimately bought the Great box, but I also upgraded my item storage twice (from 400 to 500) over the last couple weeks, and will hit 200 coins again tomorrow to upgrade my space again. I think this great box is particularly worthwhile for me because I missed the weather trio last time - getting extra access to Kyogre raids is huge! (and hopefully Groudon / RayQ will come up next for any leftover passes).