Return 1 card from your hand to your Deck. Place 1 Galloping Gaia face-up on your field from your Deck.
[...] After using this Skill, you can only Special Summon the following monsters until the end of your next turn
Meanwhile, ancient gears, shooting star dragon etc just begin with their cards already on field/grave.
And all you get is the resonator skill on a card that can easily be removed...
The card this skill searches is a +1 since you only need to reveal a card for a search. Most of the skills are hand neutral so it makes sense. Endless Trap Hell and Ultimate Dragons however are different stories.
How can it be -1 when you can literally add back the card you just returned to the deck to your hand with the field spell. I can see it happening if you're opponent goes 1st with the likes of MST and CC but those card have fallen out of favor now.
It's still -1. U return it to the deck, hence u need to search it all over again means that it cost u another card as searcher. Not to mention disadvantage that your summon locked onto gaia and BLS after using the skill also card limitation on deck while something like master of rites II, power of the dark etc. Gives you +1 without any bullsht to do.
With correct gear/equipment card, Gaia can comparable to Ancient Gear or Blue eye white dragon. But I think this skill should open to both Yugi, and you choose which one to equip when buy the desk. :)