What I would like a little more clarification on, am I doing the right thing putting it into a Roth IRA? Is there somewhere better to put my stash?
What's your tax burden? If you're currently single and making 45,000 and take just the standard deduction then your taxable income should be around $38k and you'd be in the 15% tax bracket. That's low enough that I would personally say a Roth is probably a fine choice for you.
As long as you're also contributing the minimum required to get your full employer match. If your employer were to match 5% of your salary then you should definitely be putting the first $2250 into your 401k, and after that it's probably a toss up as to whether you contribute to your Roth or your 401k. The general advice here is that for the majority of people the 401k is a better option but you might be an exception. Your tax bracket is already low and you can use your Roth IRA as an extra emergency fund since all of your contributions can be withdrawn at any point with paying taxes or penalties, so it provides a nice little cushion to people just getting started.
I think 90/10 stocks/bonds is appropriate for someone your age.
If you're getting a 5% salary match and then contributing $400/month to your Roth and then contribution $700/month to your 401k or other investment vehicle, then you're total annual savings is $15,450/year. 15450/45000 is 34% savings rate, so now you're looking at retirement in more like 28 years. That's a significant improvement. That extra $400/month just bought you a 12 year paid vacation between the ages of 57 and 69.
If you can bump your savings rate up to like 50%, a common benchmark around here, then you get to retire in about 15 years at age 44. The easy way to accomplish that is to start making more money without increasing your expenses.
