You don’t have enough BAB to take lunge at level 5.
A few things to consider:
1. Lunge needs to come at 9th level (at which point you have BAB +6). Intensified can be taken at 5th, instead. It will stack with Long Arm, so there's some utility there.
2. If you're not taking Armor of the Pit (and you probably will rely more on your magic for defense than mundane armor/natural armor), are there any magus arcana you'd like to get around that level that you couldn't at 3rd?
3. Improved Critical won't stack with Keen, which you can easily grant to your weapon using your Arcane Pool.
4. Both Staggering Critical and Stunning Critical work off your BAB. A Fort save DC 22 isn't going to net you much joy at 17th level.
For your fourth point, should I go for other feats then? Or is there a way to increase my BAB?A few things to consider:
1. Lunge needs to come at 9th level (at which point you have BAB +6). Intensified can be taken at 5th, instead. It will stack with Long Arm, so there's some utility there.
2. If you're not taking Armor of the Pit (and you probably will rely more on your magic for defense than mundane armor/natural armor), are there any magus arcana you'd like to get around that level that you couldn't at 3rd?
3. Improved Critical won't stack with Keen, which you can easily grant to your weapon using your Arcane Pool.
4. Both Staggering Critical and Stunning Critical work off your BAB. A Fort save DC 22 isn't going to net you much joy at 17th level.
Weapon Focus is a great way.....
Weapon Focus is a great way.....For your fourth point, should I go for other feats then? Or is there a way to increase my BAB?A few things to consider:
1. Lunge needs to come at 9th level (at which point you have BAB +6). Intensified can be taken at 5th, instead. It will stack with Long Arm, so there's some utility there.
2. If you're not taking Armor of the Pit (and you probably will rely more on your magic for defense than mundane armor/natural armor), are there any magus arcana you'd like to get around that level that you couldn't at 3rd?
3. Improved Critical won't stack with Keen, which you can easily grant to your weapon using your Arcane Pool.
4. Both Staggering Critical and Stunning Critical work off your BAB. A Fort save DC 22 isn't going to net you much joy at 17th level.
No.
No.The ONLY way to raise BAB is to add levels. Period. Full stop.
To be clear, weapon focus is just a bonus to attack. It doesn't actually change your BAB.
If you are bladebound, weapon focus is a very solid pick in general. You are going to be using the same type of weapon in 99% of your combats.
For your fourth point, should I go for other feats then?
Yes.
I have suggestions, but it would help if you shared your list of Magus Arcana first. Personally, if given the choice between most combat feats and Extra Arcana, I'd probably go for the latter--there are far fewer feat taxes involved that route, and more opportunity for synergy.
Or is there a way to increase my BAB?
Short of taking levels in a full BAB class, no.
I'm still trying to figure out my arcana at the moment. Of the four I can learn, I'm taking arcane accuracy at level 6 and quickened magic at level 15. A little hesitant to take hasted assault since we've got an alchemist that can craft me boots of speed (the goal is to get that asap). I'm also hesitant to retrain arcana.
Personally, I like the idea of taking Maneuver Mastery (disarm) at level 6, with an eye toward using it alongside the Long Arm spell.
I would highly recommend Spell Blending at level 9. Sense Vitals gives gives you buckets of damage every time you flank an opponent or are attacking while invisible (which you should be a lot, starting at level 10, when you can pick up Greater Invisibility). Your other 1st-2nd level sorcerer/Wizard spell depends on your style of play. Personally, I love the idea of picking up Dazzling Blade, for the synergy with your Maneuver Mastery arcana (and your Blade Lash spell). If you also take the Lunge feat at level 11, things start getting interesting.
What would you consider to be an adequate DC? Ideally I'd be making enough attacks with a high enough crit rate that multiple saves will have to be made. Worst case scenario, the debuff still happens, it's just not as strong. Appreciate the help.
This is obviously getting into ”behind the curtains” stuff, so your mileage may vary, but the average Fort save for a CR 17 monster is +19-20… so at that level, a challenging monster will be saving against your critical effect on a 3-4+ roll. So even with a full BAB character, by that level certain feats won’t work even 40 percent of the time.