Personally, I'd bring the plate (ranged).

OK, bring a fork to a knife-fight, see how you do.

Don't have many experience, but I think any strategy is, of course, personal preference. By the way, it seems to me, hordes of low level troops (e. g. 200 swords or so) gives you an advantage of numbers - you loose a little in terms of potential damage with the death of several of them, but damage is good. And don't forget the technology - bonuses to attack and defences makes swords (or spears)much less outclased.

Low level troops are ALWAYS outclassed by expert/master troops. I'd even go so far to say that two barracks worth of expert/master troops will beat out 3 barracks worth of basic troops production (though it would be a rough fight).

Depends on the specials of the more advanced troops, and the tech advantage ONLY lasts as long as your opponent having not yet bought it

This is why I once called the troop skill techs akin to the starcraft upgrade levels...they both seem largely designed to punish players who haven't got them yet, rather than reward those who DID get them