My heart breaks for your kitties! I have 2 of my own and either I'm darn lucky, or I just know cats, but I have never had these issues, tho I hear about them constantly and it really makes me sad.
First question: Do you have various types of vertical and horizontal scratching boards and posts placed strategically about the house for easy access for kitties to scratch on? (Sisal panels are best) Try placing the scratch posts at the corners of the couch.
2nd question: What is the material/texture of the new couch?? If it is very similar to their appropriate scratching surfaces, I can see where they may see it as a big giant scratch station. In this situation, you may want to invest in some double sided sticky tape(Sticky Paws), a couch cover, Soft Paws vinyl nail caps, Scccattt!! motion detector cat deterrant spray, and/or some training techniques (my personal favorite is the scruff and hiss-cats everywhere seems to understand this language)
The whole idea is to not make the new couch the most desirable place to scratch. Because it is a new object in the home, they may be marking it by scratching to accept it into their home environment. In this case, try Feliway spray on the areas that they are scratching. This will help eliminate the need to mark there.
In the case of innapproriate urination...ALWAYS ALWAYS have the urine checked at the vet's office for UTI or crystals. No amount of behaviour modification attempts will help if the problem is medical. That being said, my male cat(who does make struvite crystals and is on a special diet for it), without fail will always pee in my suitcase if i leave it open on the floor. I travel a lot on the weekends and he hates when I leave, lol

Best of luck! and please be patient! There are tons of things you can try. Also try some of Dr. Elsey's cat attract litter if the urine checks out clear with the vet.