Sh0dan as I said earlier - ships and set up in eve is PvP, but hell I'm always game 
Caldari and Ammar ships are the perfect tankers in their field. ie shield/amour. When you compare like for like, they'll out tank the Minmatar/Galnete ships. They're also designed around missiles/rails and lasers. Pulse are the short range ones, but you can't compare those to auto's/blasters. Slot wise, if you start adding ew on either you loose tank. eg shield hardeners or cap rechargers. If you've half decent EW skills - traditionally a Caldari bit of kit - you're reaching out to sniping ranges.
Now view that against the Minmatar Galnete ships. They've got a slots that are in the wrong place for tanking. They're all about gank - rather than tank. Ignoring min arty, they also radically use and have ships designed around close range knife fighting. It's all about auto's and blasters. T2 stabber might do well with arty - but I'll always fit auto's. I'll be up your exahust pipe with a TV so high you won't touch me even with a web while I'm giving you the bad news at the point of several hundred emp rounds per second. Same with the t2 pink thorax - I'm just gonna have a few more drones and it's servral 100 antimatter rounds.
Thing is tank in a proper fleet battle means jack. You get called primary and 200 battleships lock on, I don't care what tank you got. If you can't warp, your in a pod. In small fleet skirmishes, you dps ship is going to have a "spotter" it can warp in on. If you aren't using short range high dps weapons and your sniping, I'd argue your missing the point. Gate camping if that sort of thing is your bag sniping is king. But lets face it - gate camping is more PvE than PvP. It's ganking and Darwinian selection - any one with a 1/2 decent IQ will avoid or out run any gatecamp.
BUT as I said before, I'm a knife fighter - that's my "art" in eve. EFT wasn't around when I first played and neither were the auto orbits. We learnt a skill we were naturally inclined towards. Me, mines a 6km -7km manual elliptical orbit. I can't stand sniping, instintively don't get it for PvP - never will. Sure I can be told the perfect sniping set up, but I get bored and don't "feel" it in a fight. Eve ain't like WoW with the right 'spec', a good fleet commander can roll with ships specc'ed how ever the players want them as long as he can keep the ranges right in his head and manuever so targets are delievered in everyones optimals. I was beating T2 ships in T1 as they were fotm set ups against my style. eft doesn't give the feel of a ship, niether does PvE, you gotta be facing down an human to get that. In fleet battles I am that psycho in a blasterthron trying to hump enemy battleships. Live or die - I'll take a few down with me.
You also say that the lighter ships of the caldari and ammar can do the support role. Lighter ships... one or two specialised one yes. But the rest are a crock. As a smallship one thing keeps you alive - speed. That menas low mass and high speed. Hence Minmatar ships become king. That's why you see so many Minmatar cruisers in PvP now (err a few months ago). The Ammar and Caldari comparible ships are house bricks in comparision. Look at the blackbird. It's flies even worse than a bath tub. Yes it's specialised in EW - and that's the only reason anyone uses it. Only time that is fubar - is with the t2 interceptors, they for some reason don't follow those rules anymore. The claw and the stiletto should be king - but obviously ducktape has a greater mass than steel.
But... this is eve, and it is an art that eft misses. Play style is greater than substance, as if I as a knife fighter can't close with a sniper I'm dead. We'll probably not agree on ship types as I have a different playstyle and approach. Only time you really find out what works for you - is when someone is locking on to you.
Beep beep beep....