VIPRE firewall is excellent and I have not experienced many false positives; AVG generates far more false positives. However, if you want to go free then Malwarebytes, IOBIT and adblock plus are very useful and the will NOT slow down your computer by anything noticeable. CCleaner (Crap cleaner) is a great way to erase faulty files, cookies and broken links as well as source paths to infected websites.
Thus, the restoration of an infected file, whilst evidently not a good thing, is also fairly harmless because the virus is not active at that stage.
Some of the newer viruses and certainly many Trojan Horses are more adaptive and they have begun to exploit Machine learning technology, and can be extremely dangerous even at that stage.
Of course many older or amateur viruses can be kept from being active as you point out, but viruses and co-transfer of viruses with other malware more adaptable at various stages are becoming more common.