It really worries me that when someone is concerned about traffic popping up in the windscreen, people start banging on about TCAS, transponders, radar and CAS.
If you are flying VFR and paying your own way the chances of having TCAS are absolute zero - it costs more than your aircraft.
Flying VFR you cannot get a RAS.
The chances of getting an effective RIS are slim and relying on that to keep you safe is bluntly asking for a full windscreen. Apart from the fact that when it is busy - you are least likely to get that service.
The technology does not and will not answer the issue. If that is a problem - don't fly VFR in airspace lower than class D. That might be a little limiting but it is a fact of life. And that is before you start worrying about the wannabe's who barrel along in this airspace with their shiny IMCs.
Develop an effective lookout, use the strategies outlined by some of the more rational posts here and it is unlikely you will be surprised.
Understand the sky is a very big place and it is only the choke points that concentrate aircraft - avoid them.
Bluntly if you're happy with a 120 mph closing speed with total strangers less than 2 metres away on the road and not a barrier in sight - why are you worried about the tiny chances of an aerial - particularly when you take positive measures to avoid collision?