Generosity

Other than the saushIlya guNa, one other quality of Sri Rama can be considered as the answer to the question "ka: guNavAn?". In Atimanusha Stavam shloka 27, Kooraththazhvan melts speaking of this quality "kOyam guNa: katarakOtigata: kiyAn vA, kasya stutE: padamahO baha kasya bhUmi:" This is the quality of Sri Rama by which He tells Ravana who stood in the battleground having lost everything ("chachAla chApanjcha mumOcha vIra:") to go that night and return the next day. Thirumangai Azhvar condemns Ravana as "thiruvinaip piriththa kodumaiyil kaduvisai arakkan", and Kambar says "panjchenach sivakkumenkAl pAvaiyaip piriththa pAvi vanjchan". For having performed such a great sin, Rama should have killed him in an instant. Yet, he says "raNArditas tvam pravishya rAtrinjchararAja! lankAm Ashvasya niryAhi" and lets him go. This divine generosity can also be considered as the answer to the question of "kO guNavAn?".

Pillai Lokachariar's Sri Sukti

In his work Thani Dvayam, when taking up "kOnasmin ... guNavAn", Pillai Lokachariar says "sIlavaththai AgiRadhu abhishEka vignam piRandhadhenRu veruppinRiyE 'vanavAsO mahOdaya:' enRu kAdERap pOvadhu, 'AvAsam tvaham ichchAmi' enRu rishigaL pakkalilE senRu thAzha niRpadhu, 'kinkaram samupastitau' enbadhu, janmavruththangaLil kuRaiya niRkiRavargaLai 'ugandha thOzhan' enbadhu, ippdigaLAlE sIlavththaiyai mUdhaliththadhu".

Here, the phrase "janmavruththangaLil ..." has already been discussed in detail.

vanavAsO mahOdaya:

Dasaratha told Rama not once but twice that He will be crowned as the King and told Him to get ready for that. Rama accepted and was preparing for the coronation, when listening to his wife, Dasaratha told Him that He had to give up the kingdom and go to the forest. Without any hesitation Rama said that it was greater pleasure to be in the forest than to rule the kingdom. Pillai Lokachariar celebrates this great quality.

Kambar says that Rama's face was like a lotus before and upon hearing the command to go to the forest, it shone even further and defeated even a newly blossomed lotus, "appOdhalarndha senthAmraiyinai venRadhammA".

This shows that not only did He not have any concern about going to the forest, He actually was very happy to go there. Why so? If He stayed in the city and became a King, He could have only shown His greatness. By going to the forest, He can show the quality of saushIlyam, which was the goal of this avatara. Hence the happiness.

Rishis

His saushIlyam in placing Himself below the rishis in the Dandakarayna will melt one's heart. After traveling to the forest, Rama was planning to go to their ashramas and enquire about them. Before that, they came to Him and placed their issues before Him and prayed for His protection. Rama in turn sought their forgiveness in making them come to His place instead of Him going to them first, "prasIdantu bhavanto me hrIrEshA hi mamAtulA, yadIdrushai: aham viprai: upastheyai: upasthita:". This is His divine quality.

Service

Sage Vishwamitra told Dasaratha about Rama as "aham vEdmi mAhAtmAnam rAmam satyaparAkramam". Yet Rama told the sage "imau sma munishArdUla! kinkarau samupasthitau, AgyApaya munishrEshtha shAsanam karavAva kim". That is, He declared Himself and Lakshmana as the sage's servants and asked that he order them both and accept their services. This is an unparalleled great quality.