In regard to your recal after idle, the IMA system will not assist the engine at idle. There have been credible reports in regard to the 12v battery being bad and some undefined interaction with the IMA system and more frequent recals. Get it tested the old fashioned way using a carbon pile and loading it at 50% of its capacity. The newer handheld testers sometimes pass a marginal battery. Having a new battery doesn't guarantee it being a good battery either, get it tested!
I too am still a bit confused as to what valve operation you are considering. Adjustment at the specified time is part of preventative maintenance. If you don't do it then you leave yourself open to the consequences.
If you've been disciplined in the frequent oil change interval then its too soon to worry about internal engine wear.
A valve job i.e. R&R the head, cut the seats and re-face or replace the valves should NOT be done without careful consideration. Except on lower mileage cars (especially Honda) when a very rare fault related to a valve occurs and the wear on all parts is minimal. In your case and in all high mileage cars the related parts that work to maintain cylinder pressure are also worn e.g. piston rings, cylinder bores etc. To make the valves like new will increase the stress on the other related parts. Very frequently doing such a job half way has unhappy consequences e.g. oil consumption dramatically increases due to the increased stress on the worn rings / pistons/ cylinder bores etc.
A percent leak down test will give an accurate indication of the condition of these internal engine parts. Its a long story so I'll save my fingers the wear. You'll need an _experienced_ local mechanic to do the job.
As to a DIY of the IMA batteries see the thread titled:
You've heard this before, but....
In general discussion, right now on page 6.
http://www.insightcentral.net/forum/vie ... 090c975322
HTH! :)