That being said, if your interested in the liberal side of Amarrian RP, the Knighthood of the Merciful Crown is perhaps the most well known corp around, because of their ongoing... disagreement, with the other people I mentioned before.
Fixed it for you. 
I don't think KotMC would be too well known if it was just another conservative Amarrian corp.
However, playing a conservative in the Knighthood give plenty of chances for good RP inside the corp itself as we're not all just sitting around agreeing with eachother.
First off, PIE Inc. is a liberal amarr corp in the traditional sense of the word.
Just because Kotmc has decided to drop down to Ashar's level of liberality does not mean that PIE is no longer liberal... after all PIE is still on the forefront of humane slave treatment and in full support to the decrees of Heideran.
The big differences in regards to amarr rp corps today are twofold.
1.) Pure amarr empire bloodline corps (like PIE and 1PG for example) compared to open doors recruitement in regards to race (CVA for example).
2.) Liberals (PIE Inc., CVA - and on the very left end of the spectrum maybe Kotmc, although it is debatable if they still do count as amarr bloc) compared to hardliners, which have pretty much died out - except for maybe Lallara's Path of Thorns.
