I like plugins such as:
WAVES (L3 Maximizer/Ultramaximizer,..)
VOXENGO (Elephant, CurveEQ, GlissEQ,..)
URS (EQ Bundle)
SONALKSIS (SV-315MK2 Comp, SV-512MK2 EQ,..)
MACKIE "FINAL MIX"
YAMAHA "FINAL MASTER"
PSP "VINTAGE WARMER"
BBE "SONIC MAXIMIZER"
ROGER NICHOLS
There's also some freeware plugins that I like such as by "Kjaerhus" and "Antress."
Check out kvraudio.com for descriptions on these and ALOT more plugins. I believe Wavelab does load VST plugins so your good to go.
BTW, "SoundForge" and "Audition" are other good substitutes to Wavelab as far as wave editors go. I personally like Audition.