It's a straightforward enough question. I finished my first run through the game last night, and saw the credits roll. Now I have the option of continuing on to NG+, but I have yet to try using a bonfire ascetic. I swore off all wikis and guides for my first time through - I wanted to discover the game on my own - so I'm not yet clear on how this mechanic works. Should I move on to NG+ now, or use ascetics? What are the pros and cons here?

The BA just moves that bonfire area into NG+. You should only use those to re-spawn an area for enemies or items. You should move on to full NG+.

The pros of Ascetics. It lets you enjoy "NG+" content without having to deal with NG+ borked invader mechanics/hackers. It also lets you cherry pick the areas to make tougher and respawn so places you don't want to deal with again you can just farm out and leave them blank. This makes it easy to farm specific loot or get another shot at important chests/corpse items. Also f you are in the Rat Covenant for example you can use them to buff your mobs in invasion areas to crazy levels and respawn any mobs you might have somehow lost.

The negatives of Ascetics. The one time loots are still one time loots. You cant get them again until you start a legitimate NG+ cycle. When you DO start NG+ all areas +1, including any areas you already hit with an Ascetic. So you could be walking into a +3 or +4 or whatever area because you used the Ascetics for whatever reason. Also while the PVP is in many ways broken as heck and hackers run rampant on PC there are a few covenants that unless you go NG+ on you wont be able to score the PVP encounters you need to get the rank ups.

Bonfire Ascetics are great for getting NG+ gear in NG.

Examples:

On NG+, the Skeleton Kings/ Gods/ whatever drop a really good ring that increases your casting speed by 55%. Once you kill them in NG, just use an Ascetic on the Bonfire that's locked in the hut and go kill them again. It might be a tougher fight (depends how well equipped you are), but totally worth it to have that ring ASAP.

Same goes for the Scorpion Lady boss. She drops a ring in NG+ that increases your attunement slots by 3!

Are the cheaters really bad in NG+? I finished NG about 4 days ago and I'm scared to go to NG+ for that very reason. I don't mind being invaded, I just want it to be a fair fight.

I haven't gone into NG+ on PC yet myself but I have heard A LOT of horror stories. One guy in the "found a cheater" thread on this very site said after dying to a dude he literally dropped to soul level 1 and 1 in all stats. That's a character deletion right there.

@lukeweizer: I've been playing Dark Souls 2 on the PC in NG+ for about 24 hours in game now, mostly pvp, and I haven't ran into any cheaters. On the other hand, the big streamers for the game have run into quite a number, but they're all in NG right now.

At the end of the day, you'll get some degree of hackers regardless, but I think it can be pretty rare and they're mostly trying to gank new players in NG right now.

Looks like I need to go re-murder a Scorpioness. Holy shit.