I played for years with terrible defenses and a lot of deaths. Always took offensive passives and built glass cannons that always hit a wall. The passive tree really needs to be more depth than breadth first, as you seek out life nodes in other starting areas, only taking some offensive passives along the way. I think the general rule is something like 400 life per act with capped resistances (preferably from gear, but temporarily from passives if necessary). Offensive power generally comes more from appropriate support gems in linked gear, with some relatively few on the passive tree. Game became way more fun when I built defensively on the passive tree, even though it seems weird bypassing so many offensive nodes related to your skills (at least early on).
My favorite defensive base for a Ranger (Raider) is taking the life nodes and rushing Phase Acrobatics, Arrow Dancing, and then stretching across the bottom to the Marauder and up to the Scion Life nodes. “Cast When Damage Taken + Immortal Call” helps a lot too even if you lack endurance charges. At least one point of energy shield for stun avoidance, and a little bit of armour (diminishing returns) from armour-evasion hybrid gear. It’s very solid. Same idea for other classes, I’m sure.
I do wish there were an easier way to respec, but fortunately it doesn’t take long to rush the first several acts (no need to full-clear zones or really focus too heavily on gear early on). Especially if you saved some leveling uniques/rares from your first run.I ended up deleting my existing characters and starting again, this time focusing solely on defensives. I'm playing a Scion, so we'll see how that goes.
It is a little weird ignoring most of the tree. There are lots and lots of offensive talents, and they're often the interesting talents, the ones you "want" to take. However, it is very nice to take much less damage and survive more.
One of the interesting things about a defensive build is that it gives you a lot more options for play style. Offensive talents often "lock" you into a build. For example, taking talents which boost your Fire damage makes you dependent on Fire. But if you only take defensive talents, your attacks depend solely on your gear and gems. You can switch styles and abilities freely.
In that respect, defensive builds are really good for new players, as they give a lot more room for experimentation during the game.
The current structure is a bit of trap for new players. I rather wonder if the skill tree in Path of Exile would benefit from a different structure. Perhaps something where the inner ring of talents are all defensives, while all offensives are in the outer ring. This would nudge new players into taking defensives early, while they are still learning the game.