I deal with HMRC very regularly and agree with you that the service and quality of personnel is in decline.
I do, however, have some sympathy with the people at an individual level, as resource has been cut, they are not properly trained and the levels of Inspector, etc. who are able to actually help are deployed on large assignments (such as some of the ones I work on and beyond) meaning that the average taxpayer cannot access them.
I have worked in the tax profession for twelve and a half years now and the difference in quality at HMRC is phenomenal. In terms of people, it will only get worse in my opinion unless some positive steps are taken.
The worst bit it is that it will discourage the right behaviour, i.e. like you Scott, trying to do the right thing and be compliant, and encourage even more people to take the chance of non-compliance not being picked up (which inevitably will pay off for some).
What I would say is that the digital project HMRC are undertaking should be very positive. They have a team of very strong developers (I am currently arguing with some of them over a client's R&D claim!) which once they have completed their work and have the system up and running I believe will deliver a coherent solution... it's a way off though!
I could talk for hours about this and the problems in approach to tax collection at a wider level. Probably best to avoid the subject if you happen upon me at a meet as you may find tears of boredom quickly ensue...!
