Confused by your last sentence, as I see no blue -- is the fridge blue? or you're hoping to add blue?

Anyway, just wanted to say you might look into painting your grout a color to match the tile, rather than its current dark color -- would probably shave 20 years off the feeling of the kitchen. Pulls seem fine. Might do a paint that's not white, that coordinates better with your backsplash and/or floor -- maybe a nice tan or greige.

Otherwise, not sure what you want in terms of "jazz up". I might pick an accent color and work it -- a nicer patterned valence or roman blind, a rug in front of the sink, matching towels. (With your warm tones, I might go apple green, but other colors could work.) Getting a closed kitchen cart will decrease the visual clutter and give you more counter, both of which are great.

I might try to get rid of more of the counter clutter, too. Try to get some white baskets you can put up on top of your cabinets for less frequently used items, so that the rest can go into the cabinets or the new cart.

No to the cabinet hardware. What's there now is fine and is meant to be there.

Add a roman shade to your window. I think that's all you might need! Matching the blue to your fridge.

Paint is the easiest, cheapest and most dramatic update you can do. Your cabinet pulls are a classic shape so nothing wrong there. Some of your cupboard doors could use having their hinges adjusted so they hang straight, but otherwise they look fine. So colour is your best option. But what colour?

You've got white, clay yellow, terracotta and pale blue happening already. I could see you going with a mediterranean or tropical colour for the walls; something with some punch. Maybe something like this:

And remove everything that you don't use weekly to increase storage for the stuff you do use which will reduce clutter.

How about painting the walls (if your kitchen is small, you
might wish to stay with light colors to keep it fresh and open – to me, ‘modern’
is often clean lines, fresh looking.
New curtains – something simple but with color – I like the style,
and colors leelee is showing you. Stain your grout on the floor tiles - home
depot/lowe’s carries easy diy stain and it helps with floor clean up as it also
serves as a stain barrier – perhaps not quite as light as I’m showing in the image, but I’d consider a shade lighter than your tile to open up
the floor area. Clear your countertops – an under-cabinet paper towel holder
can be purchased inexpensively. Perhaps keep your chrome/brushed stainless steel items out. If your counters get water-soaked, stay away
from baskets as they’ll mildew. I like your idea of a butcher’s block trolley. Your countertops add warmth to the smeg blue, and the cabinet handles are great as is. I’ve
got your kitchen a tad matchy-matchy which I don't mind here. Perhaps add
a bit of a color pop – yellow works well with blue tho’ may look too dated. My
mind is drawing a blank.

Looks like you’ve got black and white checked baskets – are you
going for retro?

As you said, substitute a rolling cart with a butcher block top to increase counter space and storage. Look at IKEA for wall storage-they have all kinds of fun baskets and hooks you can add. http://www.ikea.com/us/en/catalog/categories/departments/ikea_kitchens/20676/

I would definitely paint a fun, bright color, add a rug in front of your sink and a pretty valance to the window.