I would say probabaly so.
Recievers always slightly skimp on the aamp and processor just to get them both in one package. I still like recievers myself, i have a Denon 3803 and think the world of that thing. Excellent piece of machinery
Adding a seperate amp would probably work rather well, it just depends on how many channels you want. If you are going to spend up to 700 bucks, then get a good used 2 channel amp and use it on the fronts, upgrade the rest later
If you spend 700 for a new 5 channel amp, you will probly get the same quality of amp that is currently in your reciever, which would be rather piontless.
i suggest you dont amp the reciver though, and spend the money on getting seperates.
Start a dedicated 2 channel system. If you start with an amp you can use it with your denon untill you start getting more of the chunks needed to get the 2ch rig running
Obviously you did not get the "format card" for question asking that David_berry passed out a couple weeks back, but it really does help if you include more of the system you are running! Plus answers from David_berry are pretty good and definatly worth listening to. :)
Peace and applesauce