Bought a new McIntosh amp

Your Rotel combo and that Rotel amp looks very desirable to me. 

I would return the McIntosh, and try different speakers as others and you discuss. My McIntosh C28 and MC2250 were bulletproof, did nothing wrong, but ......, I prefer any of the tube amps I have owned or my friends own.

Klipsch, or other efficient speakers, so that eventually you might try a tube setup.

Size of your listening space?

You have a small rear port now, and the curved back of the Paradigms has to be helpful with corners, reflections. the Flat box shaped Klipsch and large rear passive radiator are my only concern regarding the Forte. I designed rear ports for my custom enclosures, they were great in prior space, plugged up in current space. 

@tomic601 In fact, the 240 has a THD of about .5%.  It does illustrate that specs are of little use when comparing amplifiers.  Ironically, some of the most sterile and unenjoyable amps I've ever heard have extremely among the lowest rated THD specs.  I do agree that the 240 is a pretty solid performance benchmark overall.  

I would not feel any remorse for owning a MC152.  What a great amplifier.  Bought my first McIntosh piece in 1990 and still have it...along with a lot of other Mc stuff bought over the years.

Sounds like your path of audio improvements is (firmly) established based on your posts and the action of opening the sealed box and not returning the MC152.  It's great to have a path / plan.

There is a lot to be said (at least in my mind) about synergy between components.  Finding the right McIntosh preamp will be another very nice upgrade and a great match to the MC152.  Add the Klipsch cabinets that you long for when the timing is right and you'll have a fantastic system.  I love horns too.

Flip on some music, forget about what we all think and simply enjoy your very nice system.  Congrats on the McIntosh purchase!  

McIntosh builds some of the finest equipment on the market today.
Like no other brand their marketing philosophy has over the years made them who they are today. The MC 152 will give you the look but will be shy of the sound from the Mc 462 Keep in mind when you start your auditioning process the bigger the Mac the more you're going to enjoy the sound.
At your current level you will enjoy the Klipsch & Rotell. IMHO I would go with the Mac when you are ready to go big.

The most cost effective way to audio nirvana is to play the long game and make slow calculated moves. Once a new component is purchased, it takes its place and the system becomes your reference system. It will sound different than every other system out there. So then you go about characterizing what would be the next single component that would move your system the direction you want to go the most.

Spend lots of time reading professional reviews. Listen to components. But always remember when at a store they don’t have the same components and the sound is the sum of the different components… interconnects also. With the Mac you are in a whole new class of product. You should be able to bring home a preamp or have the dealer bring over speakers to test. Or reconfigure a system in a listening room to be like yours. Also, a dealer that you establish a good working relationship can help you craft the sound. It makes it easier and more fun. A dealer that knows his stuff can help educate you as well. Ideally your system can be built in partnership with one ore two dealers.

The best way to spend a lot of money and not enjoy the pursuit, and not end up with the system you want is to just rapidly swap components, unless you enjoy the swapping / high stakes game. But each move should result (more and more) in you getting the change you expected… meaning you are learning what different components in your system sounds like. In the last couple decades every component upgrade I have made sounded exactly as I expected it would. Even speakers I had never heard but read extensively about.