Here are my often used good value plug-ins:
Tokyo Dawn Labs: TDR Nova + Slick EQ M + Slick EQ GE
TB-Pro-Audio: DP-Meter II (free RMS + EBU metering)
SKnote: Disto, Stagespace, Rev250 (very inexpensive plugins but Quinto sometimes cancels further development on some plug-ins ...on the other hand he is very helpful and friendly via email)
MeldaProductions: MFreeBundle unlocked for 49,-- Euro (the Analyzer alone is worth it).
MeldaProductions: MCompare (great tool for comparing different points in your chain (with level matching and delay compensation AND you can load many reference mixes in every format aiff, wav, mp3, flac, with level matching and sync too).
LVC-Audio: PreAmped (13 preamps, 2 saturation algos, smooth EQ, Stereo control, clipper and up to 8x oversampling.)
D16: Devastor2 ...i love it!
Goodhertz: CanOpenerStudio (in my ears the best crossfeed simulation for headphones, MAC-AU only)
i3: DSP-Quattro Audio Editing (MAC only, very friendly developer, helped me out in minutes with a beta version when i found a bug in DDP-Image-Module).