This is surely good way to play Corsair, I plan to play my own in similar way. Few tips though:
- you can save few points in Iron Will when you get + skills to Defense, since those resistances can't go over 80%. If you get + skills, reduce Iron Will accordingly.
- 1 point in Batter/Rend Armor can help spread the Mandrake & Slow quickly. It's a handy skill for just 2 points, Batter even reduces attack on its own.
- Flash Powder can get you out of tight spots, 1 point can be proved useful, I often max it, you can't have enough CC (crowd control) skills
- With maxed Defiance, you can put 1 point in traps & Rapid Construction to use them as damage reflection decoys against bosses that use strong AoE attacks.
- Keep your dex high, I would go 1:1 since all melee fighters without Onslaught face difficulties with OA later on.
Start with class you find more fun, both are ok. Or if you played too many Rogues, go with Defender (and vice versa). Have fun owning