Revelle Humanities Grammar Handbook
6 Sentence fragments
7 Run-on sentences
8 Verb agreement
13 Passive voice
15 ESL
17 Misplaced modifiers
18 Pronoun reference
20a Comparisons
21 Parallel construction
23 Commas
23d Sexist language
25/6 Semicolons & colons
29 Ellipsis
31 Brackets
35 Apostrophes
36 Abbreviations
37 Underlining
39 Numbers
41b Slang
41e Jargon
41f Pretentious language
42c Idioms
42e Clichés
43a Fluff

41f Pretentious language
It is certainly laudable to expand one's vocabulary and present sophisticated arguments, but sophisticated writing is not always clear writing. Complex thought can still be expressed through straight-forward writing.

Pretentious writing: The Odyssey portrays Penelope as a relational purveyor of influence.

Revised sample: The Odyssey portrays Penelope as influential in negotiating relationships.

See also similar advice on appropriate word choices.