Check that video out.
Made by Jon The Chief it shows you how to easily complete POC with a relic in order to earn teeth however it is also a very easy way to complete POC period!
Whilst using the pistols only relic you remove the weapons challenges meaning you dont have to worry about buying a second/third gun and thus wasting cash.
Personally I prefere the turret over IMS as once its put on an electric trap it basically becomes an electrified flare and pays for itself but thats just my style of play.
I know this doesnt answer your actual question on what to spend your skill points on but if only mastering the map is your objective this will do the trick as it also runs pretty well when playing with others. Hope it helps.
I tend to start with weapon specialist up to faster reloading. Then get armor piercing ammo to 50% (you get enough money, so that's plenty for now). Then I get a second gun, usually an LMG. Then i upgrade ammo once more of fully and start upgrading vulture. I keep the LMG around in reserve, when there's a rhino, i get it out and empty it into the rhino. That should finish him off. The vulture is more practical than the sentry because you don't have to place it, which makes it more usefull in the end when you have to run. You only have to have one vulture at a time instead of two sentries, which makes it cheaper as well. It's easy to have a vulture in the air at all times.
I completed it with two and with 4 players though, not solo. With 2 persons, the other person does armor, medic, second weapon, vulture. She uses a bulldog instead of an lmg though.
hope this helps
I dont put any more than 1 point on sentries. Two is a waste of money and the AP rounds are a waste of time imo.
Personally I use the Grach pistol as it is basically an smg with shortened clips.
With a closer look at points for your setup deathrox I would stick 2 points in pistol. Then 2 in ammo. 2 in engineer for the cash back on traps and 1 on armor/ferals. At this point you should be at the 1st barrier hive with 1 point left. My play style at this point is to always keep 2 points in the bank just in case a weapons challenge comes up, that way I dont have to lose my primary with attachments to pick up a shoddy bulldog.
The second area I would be aiming to spend points on engineer first to fully upgrade, 1 maaaaybe 2 on the sentries (just make sure to ALWAYS plant on an electric trap when possible) then split the points between ammo and armor/ferals.
When I reach the cabin area I tend to place points on whatever takes me fancy once engineer, ammo and armor/ferals are fully upgraded. In this case it would be riot shield so it lasts longer, thus spending less cash.
I did a solo run yesterday and nearly got completionist (I got hit by a seeker)
I used weapon specialist, mk32, vulture and armor. And the, buy no weapons relic, as an added bonus.
When you're solo'ing, the mk32 should insta-kill anything but the rhino.
Max the mk32 first, then get faster reloading and then get some armor to protect yourself. By the end you should have some points left to max vulture and get extra speed with pistols.
You can't use armor when you have an mk32 in your hands, so that's something to keep in mind.
At first the mk32 is rather expensive vs. the little scouts, so when possible i knifed them, i tried to use a pistol on them when i didn't have an mk32 and when i did I ran in circles till I could get 2 or 3 at once.
Alternatively, skip the relic and just complete the first waves with a gun. By the time you get to the second barrier hive, there should be enough hunters and scorpions to finance a constant mk32. The last two waves, and the way back to the helicopter, the vulture can cover you.
I definitely agree about knifing the scouts when armed with the mk32. However I put my first 4 point into WS first then level the mk32. There is very little need for it until the first hive after the first barrier hive. With the quick reload speed a pistol is more than powerful enough if supplied with AP ammo to get you through the first 6 hives, and as the mk32 only has 6 rounds until the final upgrade it just doest make the money back.
Once I have fully upgraded mk32 and 4 points into WS I place 1 on my sentry for the wider firing arc and further distance and thats it. Then start on ferals, placing 2 there for the health regen. I then finish off WS. Finish off ferals and if I have been lucky enough upgrade to dual pistols for the final run back as this will rip into the rhinos and down them in roughly 3 clips per gun.
Always run this loadout on solo POC now as its beast
It's always best to first upgrade your class at least twice, because your class helps the whole team. If you're running ammo, obviously that would be your first 4 skill points. But with the sentry guns, it's truly a waste to upgrade them all the way until the last area you move into because before that, you will be struggling to afford placing 2 turrents at any point in time.