The better of them is the one who does more naafil actions
Regularly performing Sunnah actions is one of the causes of Allaah loving a person, as it says in the hadeeth narrated by al-Bukhaari (6502) from Abu Hurayrah who said: The Messenger of Allaah (peace and blessings of Allaah be upon him) said: “Allaah says: ‘Whosoever shows enmity to someone devoted to Me, I shall be at war with him. My servant draws not near to Me with anything more loved by Me than the religious duties I have enjoined upon him, and My servant continues to draw near to Me with supererogatory works so that I shall love him. When I love him I am his hearing with which he hears, his seeing with which he sees, his hand with which he strikes and his foot with which he walks. Were he to ask [something] of Me, I would surely give it to him, and were he to ask Me for refuge, I would surely grant him it.”
This hadeeth also indicates that Allaah helps and supports the one who does a lot of naafil actions and protects his physical faculties: his hearing, sight, hand and foot.
Al-Khattaabi (may Allaah have mercy on him) said:
What is meant is that Allaah helps and guides His slave in the actions that these faculties do… He guides his physical faculties and protects him against falling into that which Allaah dislikes, such as listening to idle talk that he may hear, or looking at that which Allaah has forbidden, or striking that which it is not permissible for his hand to strike, or walking towards falsehood with his feet.
Someone else said: His limbs do not move except with the help of Allaah and for the sake of Allaah, and they all strive for the sake of the truth. Fath al-Baari, 11/352.
No doubt the one who is like this, all his deeds are light (noor) and are guided by Allaah, and that increases the more naafil deeds he does.
But we cannot be certain that a particular person’s actions have more light and guidance than another’s just because he does a lot of naafil actions, because we cannot say whether Allaah has accepted these naafil deeds. This is a matter of the unseen which no one knows except Allaah. But it seems that if a person is given the choice between two actions and he chooses that which is more liked by Allaah and closer to the Sunnah, there is the hope that he will be guided and helped by Allaah.
And Allaah knows best.