-Bard is useful for solo grinding at most. as u lvl much faster and with speed(this can be replaced with drugs),and die less with noise.
-cleric is useful in solo too , as u can have more defence and recovery division and u can kill giants.
-in party playing bard is a little useful compared with cleric as it just give speed (which is useless for chinese players in ur pt) and if u gonna do tambours and dance u won't fight(except if you lvl up all bard skills to fight with which needs huge amount of sp)
-Cleric in pt FTW, for me i'd like a cleric in my pt more than a bard....as cleric can give str,int extra points(only if you don't switch weapon) , and phy,mag def.(won't disappear when you switch weapon and can be given to infinite number of players) , and with cleric u can have
45 invincble second with your pt ,and u can res other players and ress with extra hp.mp(reverse oblation) , and recovery divison help yu and ur party members with auto healing(but it makes mobs attack you) , healing skills also gonna help ur pt members 2 survive more.
-now let's talk about PvP, bard in pvp is 90% useless , it's 10% useful cuz u can run faster with it
-but cleric in pvp very useful as it help you with bless and recovery division and
OFFERING,PURE OFFERING those skills is the most damage dealers in silkroad , and the best againest more than 1 player(except if you get
blockit's up to you but my openion is Cleric+Drugs for speed is your best choice

Sorry, but you don't know much about euro do you? You are compairing apples with pears. What you said might be true for some lame chinese/euro mixed pt, but if you make it full euro you can't say one build is better then the other. If you take away the bard
then the wizards can't nuke, the cleric can't heal and the warlock can't debuff and curse. You loose alot of defense and you loose the extra damage that the dance provides.
Bards are essential for a working party and will make sure you level faster. At 90 they get mana orbit and can concentrate more on attacking then healing the members mp. With their 3 fast nukes they will do alot more damage then a chinese nuker.