I think forcing players to take 1 point in etiquette doesn't make much sense because plenty of people have no etiquette and sometimes they get away with it, other times there are consequences. It is always better to have etiqette than not and that is the point of paying for it.
Second hand cyberware should be okay I think because it is much worse than new cyberware. I don't think I would use it personally for most of my characters because I'd rather save my essence. For me, it's balanced and comes down to personal choice. I can see why you might find it problematic if players and taking cyberware from dead bodies and selling it frequently, if that's the case you could just make your npcs pay very low amounts of nuyen for it.
I also feel like players shouldn't be forced to spend any points on contacts. I consider contacts people that can do something of real value for you and many people simply wouldn't know anyone like that personally. For example, due to my line of work irl I have some celebrity friends that I can call on for favors and sometimes they ask me for favors as well. If I didn't have my particular job I would never have met these people and I don't think I would know anyone personally that could benefit me much in terms of illegal activity. Also, keep in mind that not everyone in Shadowrun is shadowrunning or planning on any kind of combat, crime etc, there are plenty of regular people working simple jobs and living simple lives and they usually wouldn't know anyone worthy of being considered a "contact".
If someone is playing a face they should have a reason for knowing all of their contacts in their background. Even if they're new to the area there are many ways to explain their connection with the contacts they chose.
I certainly think house rules are okay as long as everyone agrees. I've made lots of house rules in games over the years and in many cases it greatly enhanced the experience.