I would prefer the white but only if it's not brighter than the cabinets. Your third pic makes me wonder about that.

Agree, you can live without new back splash - just paint. Put your money towards new flooring. Such a shame you don't see they are an issue in your lovely new kitchen.

I would suggest either use the green tile or paint it the green color. The white tile, although pretty, it is going to show dirt, grease and be tough to keep clean. I am constant cleaning my backsplash.

I would do a stronger backsplash so it doesn't look so soft. A teal would be prettier or a deeper beach glass colored tile. This pic looks more blue but it is shades of teal and gray

I beg you! Skip this until you have rectified the floor? It is ONE ROYAL PAIN to rip off a splash and re do.......or to even tile yourself into a corner prematurely. Sorry......anything else is bad advice. The floor works with nothing lovely you have done, looks more tired than it is compared with your fresh new look. Paint is easy as pie in the meantime. Save Your $$$$$$$$

I would choose a longer tile. the one you have just doesn't do much. what about something like this (keeping your green tone) ?

this is a 2x8 ( which I think would look way better) Adriatic Mist

and Aspen:

this is a 4x12, frosted, Sea Foam

both are from tilebar.com they will send you 5 samples for $5.

or try a light gray

DiscountGlassTile Store

Glazed Brick in Tweed by Cle'Tile

This is the size that looks better

But Jan does have a point. The floor really doesn't look like it belongs w/your kitchen (I like it, but not with your countertop)

and just for grins, here are some other splashes w/Fantasy Brown.

Element Mist glass tile 2x6

Your right, small tiles tend to look busy. Lots of grout lines.