Another rebuild of the set (PRO TIP: build the stand first, then the wings, finally the fuselage and attachment of all the above for maximum build pleasure) and I've added another set of mods to the build.
Firstly I added an extra piece to step 18 to prevent the parts from the stand from falling off.
Secondly I've added extra rubber bands to the S Foil mechanism to provide extra stability (just grabbed one of the sets from Poe Dameron's X-WIng because I had it to hand).
Third mod curtesy of Reddit user https://www.reddit.com/user/DeductedMiller/, involves moving the engines one stud closer to the hull of the ship. This reduces the noticeable gap when the ship is in flight mode. The only issue with this mod is that it means the pins that attach the wings can't be fully inserted without pushing up the engines. Small price to pay for less gap though imo.
Mod steps 328/329, 391/392, 454/455 & 516/517.
And mod steps 345, 408, 471 & 533 by replacing the grey 2x3 plate. This allows the wings to open otherwise the part restricts movement.
This is what the X-Wing looks like with the ship in flight mode.
And finally made changes to my stand to have ship pointed downwards as standard. Bit wonky but does the job!