You are on your early stages of an Arcanist build I see. It is normal to feel overwhelmed at this stage.
If Arcanist is going to be your primary class, there are a number of possible builds that focus on the various skills. For now, in your very first try, I'd advise you to go respec most of those points and crank up the entire Panetti's Replicating Missile line (all branches including Distortion, Supercharged and Proliferation). You'll realize that only when you arrive at Ultimate difficulty will it feel a bit underpowered. And that can be easily solved.
For now, investing in secondary skills like Trozan's SI love youhard is really not necessary. Take your time until Panetti's is maxed. Then depending on whether you think you need it or not, you can invest some points in Mental Alacrity to reduce the energy costs. Next thing you should do is to try and max Maiven's Sphere of Protection (Conversion is optional, though you could put just 1 point in there if you absolutely must). It will give you the edge you need to not get squished instantly.
After this, you should try and get Mirror of Ereoctes to the level where recharge takes only 20 seconds. It is a great panic button to get you out of sticky situations. Consider investing 1 point in Nullification. It can quickly save you from harmful effects and it will peel off useful auras like damage reflection from bosses and mobs.
Next crank up Fabric of Reality and Reckless Power for added damage. It is also a good idea at this point to get Iskandra's Elemental Exchange (don't get Manifestation), Overload and Elemental Balance for more damage. If you think you don't want to spare too many points for a second class at this point, you can go ahead and max Inner Focus for that sweet offensive ability.
When picking devotions, make sure you are investing your points on elemental damage, resistances, recovery skills like Giant's Blood, Tip the Scales, Dryad's Blessing etc. For one, I definitely advise getting Elemental Storm and tieing it to your Panetti's Replicating Missile to create destruction all around the place.
The rest will depend on your choice of items. There are some sweet legendary items which could suddenly overpower you. It's all a matter of finding them over the course of time.
About the second class, possibilities are endless. I can help you again, when you decide. At this time, focus on your Arcanist tree though.