What is more essential than the chanting of the Hare Krsna maha-mantra?

For an ordinary man, worship of Sri Caitanya and Nityananda Prabhu or the Panca-tattva is easier than worship of Radha and Krsna. Unless one is very fortunate, he should not be induced to worship Radha-Krsna directly. A neophyte student who is not sufficiently educated or enlightened should not indulge in the worship of Sri Radha and Krsna or the chanting of the Hare Krsna mantra. Even if he does so, he cannot get the desired result. One should, therefore, chant the names of Nitai-Gaura and worship them without false prestige. Since everyone within this material world is more or less influenced by sinful activities, in the beginning it is essential that one take to the worship of Guru-Gauranga and ask their favor, for thus despite all his disqualifications one will very soon become qualified to worship the Radha-Krsna Vigraha.
It should be noted in this connection that the holy names of Lord Krsna and Gaurasundara are both identical with the Supreme Personality of Godhead. Therefore one should not consider one name to be more potent than the other. Considering the position of the people of this age, however, the chanting of Sri Caitanya Mahaprabhu’s name is more essential than the chanting of the Hare Krsna maha-mantra because Sri Caitanya Mahaprabhu is the most magnanimous incarnation and His mercy is very easily achieved. Therefore one must first take shelter of Sri Caitanya Mahaprabhu by chanting sri-krsna-caitanya prabhu-nityananda sri-advaita gadadhara srivasadi-gaura-bhakta-vrnda. By serving Gaura-Nityananda one is freed from the entanglements of material existence and thus becomes qualified to worship the Radha-Krsna Deity.

(Adi 8.32)