simplistic

As a verb downplay

is to de-emphasize; to present or portray as less important or consequential.

As an adjective simplistic is

overly simple.

As adjectives the difference between simplistic and theoretical

is that simplistic is overly simple while theoretical is of or relating to theory; abstract; not empirical.

As adjectives the difference between simplistic and oversimple

is that simplistic is overly simple while oversimple is excessively simple, especially so because of the exclusion of necessary complexity.

As adjectives the difference between simplistic and undefined

is that simplistic is overly simple while undefined is lacking a definition or value.

As adjectives the difference between simplistic and minimalistic

is that simplistic is overly simple while minimalistic is pertaining to minimalism.

As adjectives the difference between simplistic and simpler

is that simplistic is overly simple while simpler is comparative of simple Less complicated or challenging.

As a noun simpler is

one who grows or gathers simples (medicinal herbs).

As an adverb simply

is (manner) in a simple way or state; considered in or by itself; without addition; alone.

As an adjective simplistic is

overly simple.

In obsolete terms the difference between simplistic and shallow

is that simplistic is of or relating to simples, or medicinal herbs while shallow is not deep in tone.

As adjectives the difference between simplistic and shallow

is that simplistic is overly simple while shallow is having little depth; significantly less deep than wide.

As a noun shallow is

a shallow portion of an otherwise deep body of water.

As a verb shallow is

to make or become less deep.

As adjectives the difference between simplistic and straightforward

is that simplistic is overly simple while straightforward is proceeding in a straight course or manner; not deviating; honest; frank.

As an adverb straightforward is

in a straightforward manner.

As adjectives the difference between elegant and simplistic

is that elegant is elegant while simplistic is overly simple.