Herringbone laminate under kitchen units or not ?

If you're not going to run the laminate all the way under the units I wouldn't be bothered with tiling either if you weren't doing it yourself. A Tiler is expensive.

Each section of the carcass will be on adjustable legs so the worktops will be made level and so long as any exposed ends/sides of the units sit overlapping the laminate and same for the kickboards it'll look grand. Kickboard and end/side panels can all be trimmed so they fit flush to the floor.

I would continue the floating floor under any appliances that sit on the floor, like dishwashers. Elsewhere I would finish the floor short of the legs by the expansion amount, so kitchen first, then floor . If you tile under the units you are going to have an expansion gap between the tiles and the floating floor. There is not much room for error if you tile under the units first. Having said that I have never laid a floating herringbone floor.

Not that it prevents to floor from floating, but if there is unevenness in the floor it's laid over, it can put stress on joints leading to separation in places. Unless your floor is perfectly level throughout this can happen anyway.

I had an awful time trying to lay laminate in our living room, we eventually had to bring in a carpenter to replace the floorboards with OSB sheets before installing the laminate, even at that, there's still some sections where the joins just aren't right.

Difficult to get out if needed though, for the sake of < sq mtr of flooring.

I put in a new kitchen recently and tiled the floor with herringbone effect tiles. Tiled all the way to the skirting, imo it's a better job and with tiles there's no potential unevenness you might get with laminate. Attached pic shows a little bit of the herringbone tile, turned out pretty well.