from one 24 year old to another..
..i think you're doing great! you can probably look forward to a nice dip in car insurance rates when you hit 25 too. I would suggest increasing your roth as well. i would also suggest to buy a car strait out if you can - or at least dont go for a 15k car if all you want is a decent commute. last year my husband (who's also 24) got a new 2006 chevy aveo 4 door sedan for his 30 minute commute each day. its cute, gets about 40 mpg and our loan was only $9200 after a 2k cash downpayment. we'll have that loan paid off within the next year..hopefully sooner.. - and the car makes for an awesome sporty commute.
are you also budgeting for car taxes and gifts? whatabout entertainment? do you have a handle on where all of your spending money is going?
right now i see you only have an emergency fund and retirement accounts. you may also want to look into opening another savings account devoted to "future" wants - such as for a that new car, or a downpayment on a house..or for a honeymoon.