I'm not a bells and whistles kind of guy. Although I can appreciate extras, I tend to do things for a purpose, and if the essential reason I'm using something doesn't work well, all those extras don't help a bit.
Bicycles are a model of simplicity in design. Essentially unchanged since James Starley added a chain drive and same sized wheels to bicycles in 1883, the modern, "safety" bicycle has proven to be one of the most enduring, and efficient machines mankind has ever invented.
But the use of any machine results in wear of course, and for a machine to continue to work efficiently, it must be maintained.
Luckily, a bicycle has relatively few points of wear, and provided the rider takes care not to abuse his bicycle, it should last a lifetime with a minimum of maintenance.
What's the best mechanical advice I could lend? That's easy. Make friends with a mechanic, treat that mechanic well, and listen to what s/he has to say.
Take the time to go to a few bike shops and feel them out. Try ones that are convenient to get to, have what you're looking for, and offer great customer service.
Talk to the staff, let them know your needs, and listen to the answers. Go home, ruminate, and return only if you feel at ease at the shop.
Riding a bike will always necessitate work that you may not always be able to perform, so being able to bring your bike to someone you know and trust for this work can be a weight off your mind.
In addition to having a good relation with a mechanic, there is one thing a rider can learn that makes life on a bike a whole lot easier. Learn how to change a flat. It's the most common problem you'll have, and it'll stop you in your tracks.
There are many, great resources in print, on tape, and online, that shows how to do this simple and essential repair, but they aren't going to help you unless you take the time and make an effort to save yourself some problems down the road. Take some time, follow the instructions, and you'll see fixing a flat can be easy if you just get a little familiar with the process.
Then, the next time you puncture, there won't be a wait for a cab, extra charges for carrying the bike, the wasted time waiting for it to be fixed, or the bill for something that could have been done far faster and cheaper than had you invested a bit of your time and effort earlier.
So, keep that air in your tires, listen to your mechanics recommendations, and you'll keep rolling down the road.