This article is just for fun (except the Mantras part), as we all perfectly aware, that Krishna provides all our needs without asking from our side.
Actually, we in RAMANUJA-SAMPRADAYA sometimes follow to some special Upayas, which are very powerful, but they are not KRISHNA-DHYANAS and Gopala-Mantras, but Bhagavan Shree Vishnu Mantras, Namavalis, Sahasranams, Kavachas, Ashtakas and sometimes the Mantras of Bhagavan Shree Ranganatha.
And, of course, the Mantras of Shreemati MahaLakshmi-Devi are extremely powerful in Kali-Yuga, so once you are initiated in The Mantras of Shreemati MahaLakshmi-Devi, you don't need Upayas at all.
If you need the special Mantras of Bhagavan Shree Ranganatha, for example, for escaping from death or illness, you should ask your Guru.
And always remember the crucial conclusion of "Shree Parama-Samhita", in which Bhagavan Shree Narayana says, that actually all the Prayers and Mantras are not neccessary, as He perfectly knows what He should grant to His Bhaktas and what He should not!
CRUCIAL NO. 01: As for the list of Krishna Mantras (see at the very end the yellow excerpt from The Manuscript), the Mantras are very serious and you can recite Them, opting out the most liked from the list.
I did not transliterate, as I presume, that all These Mantras should exist for Sanskrit-reading Bhaktas.
Though One Mantra I liked very much and It is extremely beautiful, so I transliterate:
क्लीं ग्लौं क्लीं श्यामलाङ्गाय नमः
klIM glauM klIM shyAmalA~NgAya namaH
UPDATE FROM 20140722: The article, explaining the Mantra here - http://vishnudut1926.blogspot.ru/2014/07/blog-post_22.html
CRUCIAL NO. 02: Don't forget that Gopala-Mantras are extremely inefficacious WITHOUT Gopala-Kavacha, see the special article from me here - http://vishnudut1926.blogspot.ru/2014/05/shree-gopala-kavacha-without-this.html
From "Krama Dipika" - Vaishnava Agama with Gopala Mantra Glosses
(the link to The Book - http://goo.gl/t3VsRM):
"The uses to which the Mantra can he put are various, but for each different application of The Mantra a different Dhyana of The Deity is prescribed :
DHYANA FOR FOOD:
(1) If one is in need of food his dhyana should be that of Gopala-Krishna lying in His cradle, gently swayed to and fro by Gopis and fed with milk.
DHYANA FOR ILNESS DESTRUCTION:
(2) If it is desired to allay adversity or illness or misfortune, the dhyana of Krishna killing Putana is advised.
DHYANA FOR LONG LIFE:
(3) Long life and good health are obtained by meditating on Youthful Krishna carrying milk and curds in His Hands.
DHYANA FOR THE CURE OF POISONING:
(4) By meditating on Krishna dancing on the hoods of Kaleya, maladies caused by poisoning are cured.
DHYANA FOR CURING FEVER:
(5) Fever among children is allayed by meditating on Krishna holding the demon Baka by his beak and tearing him to pieces.
DHYANA FOR DISASTERS:
(6) Distress caused by excessive rain, storm or lightning is averted by meditating on Krishna holding up Govardhana with His Left Hand and playing on His flute.
DHYANA FOR RAINFALL:
(7) Rainfall and relief from fever are obtained by meditating on Krishna, sporting in the Shree Yamuna with Gopis and sprinkling water on Them.
DHYANA FOR SHATRU VINASHA:
(8) By meditating on Bhagavan Shree Vishnu riding on the Garuda and routing His enemies, one's opponents are vanquished.
Similarly special Dhyanas of Bhagavan Shree Vishnu relating to the Various Episodes of His Life are prescribed for numerous objects such as securing prosperity, attaining to the office of the high priest to the king, obtaining children, gaining mastery over eloquent speech, bringing people under one's influence as also for attainment of freedom from the sorrows and miseries of the world.