Origin client is malware. If it's not spyware as suspected, it's definetly bloatware/adware - every now and then it advertises stuff aggresively and without any criteria. For example I don't want to see any advertisments on EA MMOs, thanks to that malware I see those news frequently. Their cretinism is also the reason I refuse to receive EA newsletter.
It's cloud/downloader parts are not as good as Steam's, but still works better than uPlay and GOG downloader. While uPlay and GOG in case of hash check eroor force you to redownload everything, Origin will "fix" just the corrupted part.
About it being possibly spyware… I don't really care if it sees or not what's on my PC. You can also come to my house and knock yourself out browsing my files, I don't care nor I have a need to hide anything. I didn't put a password on my rig nor on any single file. But it's a home PC I don't use for contracted work and stuff thus I do understand people who don't want spyware and IMO if it spies on data, EA should be sued.
I let it run automatically when I turn on my PC. You can change that in options or simply uninstall it when you're not playing some Origin DRM game.
On your last question I can provide only subjective answer. In my case, Origin is not really that bad. But neither is uPlay.
Would my life be happier without those? Most definetly.