The ‘lag’ argument is quite misinformed. Bukkit’s chunk loading is threaded, it’s effect on the actual server tick is nowhere near as drastic as is being made out.
I recommend to any builder to utilise a flymod where they can. It allows for quicker assessments of builds both from a distance, and at various angles. The process of making adjustments & checking them becomes much more fluid (more time thinking/building, less time fighting with vanilla's slow, clunky creative flight) - which can help produce better looking stuff in the process.