Allods Online Forum

for "being useful" engineer is the best class i guess as it has awesome buffs which is a great improvement for endgame content
bard is similar but it is inferior to engineer

soloing & proper leveling is possible with EVERY class, you should only make sure to have enough of the "bloodlust" stat to make sure you heal up enough, thats the "secret" of fluid leveling
also make sure to level with aspect of assault (sword symbol), get this at rank 3 as soon as possible
it is NOT recommended to level with any other aspect (suppression, support, tank) as this usually will result in poor damage and high frustration (unless you exactly know what you are doing but thats not topic here)

those who lack bloodlust will have to regenerate health with salvation of martyr skill every few mobs which is not very pleasent

the best classes currently are paladin and scout, warrior is great aswell - these are durable, do high damage and are easy to play - they are vastly superior - however this is related to PVP especially

fastest levelingexperience is definitely psionicist (i have leveled 15+ chars of different classes to max) as it is the class that kills much quicker than all others along with all the phantoms, works like cutting through butter with a hot knife