More Strategy Help (in General)

Most of the clan members around my score are using some form of melee or archery, I often lose to these characters, and I was wondering if it would be wise to train a little ethereal chains onto my minion with ablative shield.

completely terrible idea!!!

mind you i'm one of those characters training archery that you're probably talking about so take my opinion with a grain of salt :p

EC will kill a little of their dex and str so if thats the goal then do it

no :P training a little EC will do very little. If you want to survive longer train more AS on your AS minion ><

If you don't train DX on any of your characters, the only way EC would be effective in avoiding any hits if you get enough to bring enemy DX into the negatives... and since damage per hit is only partially affected by ST, you'd need to bring their ST down to near-zero too to make a difference.
So, while in theory it will work wonders against a team with more than just one tank, it will be a failure against ToA teams, and a spectacular failure against solo ToA minions.

Also... you're talking about "around your score"... well, you have 2.2 mil score, and below 600k MPR... of course most clan members around your score will beat you senseless, there's plenty with nearly double MPR :)