Fix too small bike with stem and handlebars?

I made a misstake and bought a bike which is too small for me, the Breezer Radar Cafe size M. I'm fairly certain I want to move the handlebars about 2-5 cm forwards and around 3-5 cm higher. I can't really say exactly how much I want to move the hand position until I've tried different fittings but I'm comparing to my old bike, which is a bit too long.

When looking at their size charts it seems like the L model will only give me 5.6mm longer reach and 4.4 mm longer stack but I can't visualize how much of a difference that would make and I don't have an option to test ride one plus I would have to trade in the one I bought.

I like the bike concept, the wide tires and the maneuverability. I like the low stand over hight which suits me fine in the city but I feel cramped when riding it and I can feel an unpleasant tension in my shoulders and neck even after just a couple of km.

Is it possible to fix the bike with new stem and/or handlebars? Will it affect the steering in a negative way? Should I even bother or simply try to sell it now when it's new and minimize my losses?

My options now are to either try to fit this bike, sell this bike and look for a new one or sell this bike, invest some money in my old bike to find a fit I want and then wait until spring to get a new bike based on the changes I've done on my old one.