I could have sworn I had just seen an edit about formatting variables into text. There are a couple of ways to go about it. If you just have the one variable to insert, it's easy enough to use:
For your string. If you have a lot of things, you might want to use string.format()
Though really, it's often a matter of preference. If you're doing a bunch of string repetition inside a loop or something, string.format() is faster iirc, but other than that it's six of one, half a dozen of the other. You can use "" too, but it makes it more difficult to use " themselves inside of the string.
As regards the variable names, if you haven't already you may want to read The Shared Namespace And You
which is an excellent post regarding keeping your stuff compartmentalized inside a table (exactly like I didn't in this post... bad me)