Not by RAW, but if your GM allows it
Since the spell name says its a weapon, hoverboards and pillows are probably not intended.
By RAW, it seems that one cannot physically interact with the weapon at all, except when attacking someone. This was discussed in this question and is also evident from the description which says a "spectral" weapon.
Concerning the form, the description suggests that it takes any form of weapon since that is the intended use of the spell and since the description gives examples of weapons, e.g. hammer.
Pillow fight is just flavor
Then again, your GM can allow any creative ideas you can come up with. The example of the pillow might or might not fit the tone of your game, but it does not have any balance implications if you do not change attack modifier, damage and so on.
Other things give new powers to the character
"Hover sticks" and ladders give the spell a lot of versatility that is probably not intended, but your GM can totally allow this. Anyway, they already gave you poledance proficiency which does not appear in the rulebook as far as I know. This seems to indicate that your GM has no problem with new ideas and that the surfboard and other stuff might fit the game, so you should totally ask them. When implementing / allowing this in the game, it is important to bear in mind that a) this only fits a game where creative ideas trump hard rules, and b) that allowing this might favor you before other players unless they can also gain advantages by bringing creative ideas on the table.