My ever changing own personal take on Shulk is pretty gimmick-less, except for some specifics of moves. I've yet to take the time to make up his tilts and airs, and some specifics aren't fully fleshed out yet, but it's what I have so far.
General Attributes
His smash attacks would be stronger than most other sword users, but not as heavy hitting as someone like Ike. He should be fairly quick on his feet. Faster than Link but slower than Marth, with his attack speed being somewhat below average because of the general nature of his attacks. He would have decent jumps, with his first jump gaining most of the height and his second jump being significantly less powerful. His weight I imagine would be around the middle, so he's fairly easy to knock off at lower percentages (85-100%) depending on the attack of course.
Standard Attacks
Jab: Not a jab combo, but rather one solid, diagonal slash meant to space more than anything.
Side Smash: Back Stab. A quick forward stab that does more knock back and damage (about 1.5 normal) on the backs of enemies. Reliable kill move at higher percentages, sends opponents at a straight horizontal trajectory.
Up Smash: Two handed stab at the air with the Monado. This is a good kill at all percentages, and charging it increases the range, not the power. The farther from the base however, the weaker the move.
Down Smash: Stream Edge. It is a low angled attack that trips if sweet spotted and knock opponents diagonally upwards if not. Combo starter at low percentages, decent kill move at higher percentages.
Specials
B: Monado Armour: A shield surrounds Shulk for 7.5 seconds, giving him flinch-resistance to weaker attacks for that time period. Stronger attacks will still affect Shulk, but not break the armour.
Side B: Monado Eater. Shulk blasts ether energy in front of him in a gaseous cloud, trapping enemies in in for low damage while inflicting the enemy with a bleed effect similar to White Pikmin which last for 5-10 seconds depending on how long the enemy stays in the cloud to begin with.
Down B: Monado Cyclone. Shulk charges before releasing ether particles which completely surround him. Very slow attack with a lot of cool down, but has incredible KO potential.
Up B: Monado Speed. Shulk darts quickly diagonally in the direction he is facing. The angle of recovery can only be made purely vertical, or purely horizontal by tilting the stick in either direction, but Shulk is entirely invincible during this time. However, pressing A will stop Shulk and cause him to do a quick spin attack.