Never once had any problem of any kind on any of my Nexus devices. The list of people I know who've switched from iPhone is pretty big. That said I do believe in horses for courses and what's right for me isn't necessarily right for you and vice versa. I run hardly any apps as stock covers 99% of my needs and I install the odd thing for a bit of fun, testing or tinkering with.
Chromecast, for example is freaking awesome since the last update. You should really check it out.
Controlling my home pc's or parent's pc's from my phone is pretty slick too, I've never seen such a simple implementation of RDC. I use it constantly.
Probably not the best time to upgrade mind you. The new Nexus is rumoured and you'll have the new iPhone to choose from by probably next month.
Best advice if you can't wait would be to go to a store and try out each of them and see what suits you the most.