No, no it really isn't. VII and VI are my two favorite FF games so I would know; they're very different games. The stories play out completely differently, the characters have no analogues between the two games (i.e. there's no equivalent of Barret in VI and there's no equivalent of Sabin and Edgar in VII) and the gameplay, while somewhat similar with the Espers and Materia, ultimately feels very different. 4 characters vs 3 characters for one. FFVI is much more magic-heavy than VII; most of the time you can win battles in 7 with a relatively simplistic strategy. Most of the difficulty in 7 comes from preparing for battle properly (although to be fair, you can completely break 6 with Ultima). Also, for a very significant portion of VII, you're forced to play with a pre-determined party, like that big chunk towards the start with the three parties or when you first wake up in the WoR with only Celes.

Also, VI is not better, especially in the story department (IMO). Most of VI's plot events are crammed into the first half of the game, while the entire second half is very character-focused. You see little to no character development in the first half, and very few major story events occur in the second half, whereas in VII, the two are intertwined (quite beautifully in fact). It's one of the best things about VII. Sure, the translation is severely lacking in the original version of the game, but VI's is far, far worse in the SNES version. The plot is very complex and the twists are quite unique without feeling unwarranted. I can understand if you don't personally enjoy it, but that doesn't mean that it's a bad story. The only things I like better in VI than in VII are the graphics (I prefer sprite-based graphics to garbage-quality 3D graphics) and the difficulty curve (although the final boss itself is disgustingly easy). Don't get me wrong: VI is my second favorite FF game. It's just that it's second to VII for a reason.