Panel in the rear quarter lights by boxing in the rear arches, extending up in a tapering, sweeping curve to the gutter line. Extend the 3 vertical swage lines in the bootlid up into the roof so they split the rear window into 2 quadrant shapes, (bottom of the rear windows straight to match the top of the bootlid). Paint the roof brown so it's part of the body. Raise the bumpers level with the bodywork instead of hanging below it. French new circular rear lights into the rear bumper & paint the bumpers body colour. Half French the front lights into the front wings, so they're still obviously Citroen originals, but level with the top of the wings & partly set back into them, (think the front indicators are already partly set in aren't they? So they'd match). That'd lose those horizontal light mounting bars that spoil the curves at the front. Lose the plastic grille shell & cut a new one into the bonnet in the shape of the Citroen chevrons. Back it with mesh, painted black & maybe highlight the edge with chrome edging trim or add a raised lip around it in 8mm round bar painted body colour.
Or slam it to the deck with full skirts on the front wings to match the rears, then paint it white with blacked out windows & some sci fi accessories, fake jet engine cowls etc to create a Star Wars type hover vehicle.
Or play up it's quirky shape & go Steampunk, with lots of brass detailing & fake cogs & copper tubing & a polished wooden dash full of antique gauges, with sumptuous Victorian red velvet seating, (think Jules Verne's time machine in the film).
Lots of potential, but like the Minx gasser, I reckon you need to commit to it & go over the top to properly pull it off.