Well obviously the Classical Defense is a sound option (otherwise it wouldn't be known as the Classical) in the very same way the QGD: Orthodox Defense is also very solid (otherwise it wouldn't be Orthodox)!
In my experience, I enjoy playing the Berlin Defense (1. e4 e5 2. Nf3 Nc6 3. Bb5 Nf6) as Black because it has lots of tactical situations when playing against a less experienced player, and it leads quickly to a solid endgame against a seasoned tournament veteran.
At the Super-GM level, Kramnik turned this defense into the "Berlin Wall". This combined with the Petroff led to solid draws as Black against Kasparov, and with the Bayonett Attack as White, it led Kramnik to dethroning the great master.
Personally, I love almost any defense in which Black has an opportunity to play Nf6 and Nc6, especially early. I feel a sense of calm and sort of zen or feng shui feeling come over me. It's as if the Knights are going to the squares that the god(s) intended them to go. But that is but a personal quirk of mine . . .
In general, I think the test of adding any opening to your repertoire is whether or not you enjoy playing the positions that arise when you face off against better players. I've been experimenting with the Caro-Kann for a few months now. And I like the positions that arise when I play people with 1000-1600 rating or so. But when I play against 1900-2200, I'm not 100% sure whether the opening is for me yet. Of course the Classical Defense is going to look good against less experienced players because it is rock-solid and gives you a solid position with which you can use to build a lead and convert it into a win. But you might not enjoy it as much playing from behind.
Is the Classical Defense of the Ruy Lopez considered solid? So far i'v had 2 games with it as black and won due to the endgame (My strength in my opinion is the endgame).. Usually it leads to boring but solid play for black and usually drawish, but this is the safest variation i can find for black in the Ruy Lopez.. what do you guys think?
These are the only games i actually played e5 in (except in the past, 6-12 months ago)
1. e4 e5 2. nf3 nf6 3. Bb5 Bc5
Also what variation do you guys think is solid?
Here is the 2 games..