> Are there any reliable ways to get answers to such questions from people who are experienced?
In my experience, the challenge with soliciting this kind of feedback is in filtering the responses. Opinions are formed for a variety of reasons. Some are well formed from experience, while others are simply dogma:
Authority Figure X says to use Solution Y.
or cargo cult:
Successful Company X uses Solution Y, so you should too.
It's worth considering why authority figures recommend specific solutions, but that informs you as to the reasons why you should use a particular solution, not that you should always use a particular solution.
Giving a good recommendation first requires that the offerer of the opinion have the qualifications necessary to be considered an authority on the problem domain; second, that they invest the requisite time in understanding your unique set of circumstances; and finally, that they are prepared to set aside any dogmatic beliefs they have developed along the way. You must be prepared to filter the opinions you receive in order to avoid incorporating advice affected by these shortcomings.
Rather that solicit advice on your entire infrastructure, you should do two things:
1) You should seek to understand the technologies you're implementing to a depth that allows you to identify potential pitfalls. In other words, understand what a particular solution is good and bad at.
2) Try to hire/work with people who specialize in specific problem domains. A jack-of-all-trades can only have so much depth.