For my own education and just for fun, I occasionally write small software applications.
Lately I've been considering taking the next step and polishing one or more into something that could be useful to a broader audience. One possibility is to found an mISV and charge for products.
I'm not an entrepreneur by nature, though entrepreneurship fascinates me.
Am I just asking for trouble by taking on the very non-trivial business aspects required to succeed?
Have you considered making these apps available as shareware or donationware? It's not as popular as it once was, but setting up a website where people can download your apps and pay or donate via PayPal should be easy enough.
How would you define success? If you're having fun & only a handful of people buy your apps, then you haven't lost anything. Start small & if there is a demand for what you're building, then worry about the business details when the need arrises.
It's a really hard question to answer without knowing who you are, how you define by success and what 'trouble' means for you.
Try making a list of all the pros cons of (1) and (2) not trying. You could try thinking about the different scenarios too. E.g. (1a) - you try and it's widely successful, (1b) - you try and a few people buy it, but not money. Think about how you'd feel in each scenario / how likely each scenario is.
BTW, don't worry if you're 'not an entrepreneur by nature'. Very few people are born that way. Sure, you need to want to do it and have the seed in you, but it's something you learn.
Why would you not want to make money off a hobby that you do for fun? People have always said (my mother at least) that hobbies do not make money, but if it does why would you pass it up?
I would recommend taking it slow though as you sound a bit hesitant, pick your favorite software and start polishing it and see how it goes. Then get the rest of them ready as time goes on at your own pace.
You are not asking for trouble at all. It is very natural to want to take your hobby to the next level, and to see if your peers appreciate your work. If people are willing to pay money for the software you write, it means that your software is as good as you believe it is, and outside recognition for success is a great thing. (The same can be said if you have many users if you give the software away for free).
One important element that will effect this that is beyond writing software is the marketing. If no one finds your product, no one will buy your product. While marketing is not rocket science, it is something that requires time and hard work, both in learning how to do it correctly, and in executing what you have learned. The bright side of that is the fact that you will get money for your trouble as compensation.
Figure out if you want to take the time to learn the marketing and sales skills needed to make it work. You can ask the people on this site what it takes (there are several questions on the subject already). If you choose not to take care of the marketing yourself, I would suggest partnering up with someone who would know how to market the software. You don't need to pay this person a salary (unless he gives you a one time consultation) but rather they should be compensated with commissions.