Command line Haiku is pretty much identical to Linux so if you get comfortable with it on Haiku then Linux will become much easier for you.
BTW: If you are interested I ported the command line Amiga module player/emulator to Haiku a few weeks back.
http://ports.haiku-files.org/ticket/695
First off, COOL MAN! I didn't realize you coded, didn't realize you were a Haiku user either!

Secondly, I don't mind a little command line here and there, I've used it plenty under all the Amiga OS flavors as well as on Haiku. I find it enjoyable for basic needs like launching a game of Odamex with a special file attached. Or better yet, I like creating scripts for my Amiga Icons to launch pWADs and such for Odamex or what have you.
What I hate is when my system isn't working quite right and I have to fully depend upon a crap load of command line entries in order to work things out, and I hate it even more when I get strange and elusive error messages that only the seasoned Linux user understands. That is when for me, Linux ceases to be fun.
Others may like that depth of control and I think it is a nice option, but to be something that is still mandatory, that is annoying to me.
Another thing that makes Linux confusing is all the distributions, built upon this kernel and that, this GUI and that, so on and so on. It's like there is no standard...
Long live Haiku! I can't wait to see how things go after 1.0 hits the net!