You could try a compressor with lookahead and a ratio of about 3:1 low threshold (compressor practically always doing something), long release (1000-10000ms) fast attack (0.2ms), try waves C1 ... should keep it all up front. Otherwise you could always load the thing into a sequencer type program and draw in volume changes where needed.

Wack the thing through a touch of L1 ultramaximiser afterwards but don't over do it or it'll sound horrid! Remember (as bob katz would say) that you aren't trying to make the hottest CD ever, people have volume controls and can just turn the thing up if they want! But making the levels so it never feels like it goes quiet on you is probably important ... manual tweaking would probably give the best final result.

You could do C1 in addition to what MigL's talkin' about up there. I'd do any manual level riding and/or the C1 trick first before the other processes.