With such limited room by the doors, and no need for cold weather storage, I'd forego any storage. rather put a nice bench in your living room where you can store shoes/purse etc. It can serve as seating and storage.

That is a tight space and no matter what you bring into it, it will look cluttered. If you must have something, then add an over the door shoe rack onto the door to the laundry or put up a rack for coats, on the opposite wall add one or more of those shelves that have hooks, you can add baskets to the top and put the family member names on them to store their stuff.

The easiest solution is that you could have a single shelf -- box -- built above the front door with a door for the box with a hinge at the top -- but this would only work for those tall enough to reach over the door. Painted the same color as the wall, it could disappear -- or you could include a ledge atop the box and risk putting something atop. [You might consider a rectangle planter box with ivy and something for it to climb on toward the light of the window. You'd need a ladder or step stool to water any plant you put there and might want to invest in one of those colorful glass globes with a long stem that stick into the ground and slowly water the plant as the soil dries.]

IF ... huge if ... you were willing to invest in altering at least the several steps at the bottom of the stairs -- and if, as is likely, there is empty space below them, then you could have wide drawers placed where the risers of each step are.

Less practical (unless you want to risk getting bonked in the head) you might could create a cabinet above the front door (below the window) that lowers with the flip of a switch (doors would need to securely latch):

... one that would pull down (think... murphy bed hinges ) that could do a full 180 to come to rest in front of the closed door; or

... a cabinet that would drop straight down after you close the door (think... mechanized dumb waiter).

Don't put anything on the walls that would stick out that you could bump your head or shoulders on.

Edit to add: actually the easiest "solution" -- other than just taking off your flip flops and carrying them upstairs -- could be to...

... put your flip flops bottom-to-bottom and set them on one of the bottom steps under the handrail against the wall; or

...hang a "hammock" over the door and toss your flip flops in it and have a bamboo pole leaning in the corner behind the door that you could use to bump them back out again; or,

...add an eye hook to the inside of the door and hang thereon one of those cloth bags to hold plastic bags (recycled plastic grocery bags) that you could each take one and put your flip flops in it as you enter either to leave on a step or to carry up the steps, with a place atop the steps specifically intended to put those bags; or,

... affix a shallow "mail box", with lid, painted white, to the inside of the door that would hold a couple pair of flip flops (door likely would not fully open).

Edit to add:

If there's room on your doorstop outside and no rules against it, build a box with cabinet door(s) below (preferably lockable) and set a plant atop it.

HI -- IKEA has these wall mounted shoe holders . They pull / tip open like a mail box , they come in a white plastic and hide the shoes away . You could put them on the walls just under the hand rail on each side or on the left wall . Ikea also has great coat hooks for the garage door or just in the garage by the door out of site . Next time you paint , do a washable flat or pearl finish and have the walls and handrail and trims the same color . The paint finish now is very shiny. Maybe add some mirrors .

Very special thanks to everyone who responded to my post. You have shared some terrific ideas ...appreciate you taking the time and offering your ingenuity to address my space dilemma!