What is the best non-degradable armor for runescape with my stats?

Your setup is pretty much okay for now, factoring in your stats and how much you're willing to spend. Possible upgrades include:

Helm: Dragon Helm has slightly better stats. You can sell your Helm of Neitiznot for about 30k and get a Dragon Helm for about 60k.

Gauntlets: You could switch out your Dragon Gauntlets for Black Spiky Vambraces. The Vambraces has slightly better stats and costs only about 3k.

Consider getting a set of full void melee armor. (Void melee helm, Elite Void top, Elite void bottom and Void gauntlets). Although the armor rating and life bonuses provided is lesser, it will add about 10% melee damage and 10% melee accuracy bonuses.

As for F2P money making, you could try this method, one that I personally use a lot. If you can find a crowded Firemaking world, you could just pick up the ashes and sell it. Assuming, there's no one there to compete with you, you can pick between ~1000 to ~1100 ashes per hour. Ashes are going for 359gp per ash at the moment, so every hour your profit stands at upwards of 350k per hour. Pretty decent for F2P, yet still requiring no skills at all.

As for P2P, I'm not sure. Sorry.

Well bandos is awesome armour and you can earn the money for it rather quick, might take maybe 3 days for both bcp and tassets if you have some good luck - head to brutal green dragons in the Ancient Caverns - Other than that you could always go to pest control and get full void, looks great and has some good stats.

Grotworms

Helm of neiteznot isnt really good any more i reccomend using a dragon helm or barrows helm, depending on how much cash you're willing to spend. BGS is probably best for you allthough i do reccomend trying to get 80 att to get chaotics, instead of dragon defender id use a 2h wep or an offhand weapon allthough theres not really a good level 70 offhand apart from the enhanced excalibur which has lots of extra reqs. Either granite chest or a barrows chest depending on money. dragon legs or barrows, money again :P to be honest you cant really upgrade you're armour much with out more money.

The way that you can make the most money (aside from pking) is PvM, unfortunatly to make LOTS of gold from stuff like GWD and Kalphite King you need really high stats (92/95 prayer 90 combat stats etc), i suggest you try and train your att str and def all to 80 through slayer and then get a chaotic maul from dungeoneering. Until then you wont really make that much money.

------To make some cash at your level, get some friends and go to KBD, every kill is worth probabbly around 6/7k and they can very rarely drop some stuff worth 1-3m