Rama is glorified and Ravana was condemned as an evil by Tamils. There are some attempts to project that Ravana was considered as a good person and some people even say that Jain and Buddhist versions have a positive approach towards Ravana. ( but no supporting proof is given by them )
Now let us see what the other texts excluding Vaishnava literature say about Rama and Ravana.
Let us first see Saivam -
Sambandar.
Sambandar refers the incident of Ravana singing Sama Veda to please Siva.
சாம வேதமொர் கீத மோதியத் தசமுகன் பரவும் (2-92-8)
But at that same time, he refers that though Ravana mastered the Vedas, he did not understand it's true meaning and his actions were actually against the teachings of Vedas.( Urai unaradhavan)
மானன நோக்கியை, தேவிதன்னை, யொரு மாயையால்
கானதில் வவ்விய காரரக் கன் ( 3-10-3)
உரையுண ராதவன் ,காமமென் னும்முறு வேட்கையான்
வரைபொரு தோளிறச் செற்றவில் லிமகிழ்ந் தேத்திய
விரைமரு வுங்கடலோதமல் குமிரா மேச்சுரத்( 3-10-4)
உரையுண ராதவன் - One who did not understand the meaning/teaching (of vedas)
Buddhism
How the Buddhists refer Rama and Ravana?
Manimekalai சமயக் கணக்கர் தம் திறம் கேட்ட காதைWhile explaining various religions ( here religions are various sects like Meemamasga, Mayavad, Saivam, etc)
While explaining various logic, there is a statement - " when some one say that Rama had won then it implies that the Ravana who did not have any charectar (மாட்சி இல்) had lost."
The one who is with great people are always benefited. - Like the younger brother of the King of Lanka who became the king of Lanka by being with Rama.
A Jain text calling இராமன் as பெரியோன் andindirectly referring இலங்கைக் கிழவன் as கீழோன்.
All the religions of that period had glorified Rama and treat Ravana as a person of lower moral charector.
Religion, as we understand based on the Western constructs, is a wrong word for various Indic traditions and philosophies. Please read Prof. S.N.Balagangadhara's views on why Indian subcontinent did not have any religion.