Looks good to me, I'm pretty sure you'll like it. If you really want to go with the mobile athlon you can, the wire mod is no really hard, its pretty simple actually. You can run the mobile athlon without the wire mod as well, it just that it runs at a much lower speed. You can look at this thread and get a better idea of the mod you would have to do.
Asus Micro Mobo and AMD XP-M 45W Barton
Then again if you don't want to hassel with doing any modification, you could always contact Opus and see if they can correct the problem in your current power supply to work with the Biostar board. I don't think they would charge you much.
Asus A7N8X-VM - AMD Mobile Athlon 2400
512 Ram - 60GB HD - Opus 150w
Lilliput 7" - Rikaline 6010
[00000000000001100010-] 98% Completed
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