Kitchen cupboards and cooker hood outlet

I'm planning to look at fitting a set of kitchen cupboards (wall and floor) and associated appliances soon which have come from another kitchen so they weren't designed for the space they'll be going into but so far it looks like should go in ok..
The existing kitchen (that the cupboards are to be installed into) currently has a cooker hood mounted on the underside of a cupboard that bridges that gap between two other cupboards, the vent passes through this central cupboard and the pipe then runs along the top of the cupboards to the wall - similar to this: https://www.diynot.com/diy/media/untitled.10078/full

The 'new' cupboards don't have this bridging cupboard arrangement, so my current thinking is to either box in the vent pipe where the wall meets the ceiling (like this: https://i.ebayimg.com/00/s/Njg0WDEwMjQ=/z/nOwAAOSwfZhXNF6Q/$_86.JPG) or perhaps go into the ceiling void (assuming the joists are in the right place, they run the right way I know that much). Has anyone got any other ideas? Or see any problems with either of those options?

Cheers!

Will the unit be on an outside wall.

Unfortunately not, the hob/cooker hood will have to back onto an internal (paramount boarded) wall

Use a carbon filter ?

Change the round extractor hose to flat channel, and look to use a fill in piece across the top of the gap, and the carry the cornice across the complete front of the units and the fill in piece.

dpsservices said:

Use a carbon filter ?

Click to expand...

Oh like a recirculating hood instead of venting to the outside? Do you not get increased condensation from steam?

Therein lies the problem with the recirculating types, plus the cost and mess of changing or cleaning the fliters.