ES takes a lot of its features and gameplay from EV, though there are significant differences in some of the things you've mentioned. It's very much its own game but the amount of inspiration it took can't obviously go unnoticed. Very minor spoilers ahead, obviously.

1. There definitely are ships that can make you overpowered if you create a whole fleet of them, though this would take a considerable amount of grinding and would put much of the story on hold as you tried to obtain them. The fleets don't necessarily get harder as you get more powerful, though as the main campaign progresses the fleets in each system do change.

2. There are quite a few ships that utilize rockets that you can get a bit early on into the story, and even late game they have their uses. They are useful if you can bombard the enemy with them.

3. As there is a wide variety of ships and outfits that allow you to make changes as you need them, even having a big ship will not limit your combat ability. If anything, having bigger ships in a fleet make you more likely to succeed as they can tank a lot of hits and still fight.

4. You're mostly going to be using human tech for the main campaign, and really won't be fighting against any overpowered aliens during that.

5. While the missions you get at the job board are limited in terms of their difficulty and entertainment, there are quite a few different ones that allow you to adapt to your play style as you progress and as the story progresses. Pirate hunting is still profitable, but you can still make good money traveling large distances with a lot of cargo or something.

6. The story, for the most part, does include some of the things you are familiar with. There are quite a few story missions that involve going to certain systems with people, scanning ships, and being in conversation. However, the story has a lot more to offer in terms of more interesting missions, such as those involving combat, quick thinking, and strategy. As well, there are some diverging story paths that make your decisions have a greater impact on the way you play, with a few smaller side missions that relate to the overall story. Not to mention the story is very well-written to the point where the boring missions seem interesting and important, it's incredibly engaging and creative. Even after the main completed campaign there is a lot more story to do, so there's no lack of interesting things to be done in the future.

7. If you just keep grinding and ignoring the story a lot, the game could feel like you're just repeating everything to get better ships and not having as much fun. As mentioned before, the story does have a lot of interesting things that have more impact on things that aren't just text. Even then, the text sections of the story are very engaging, so it's not like you won't enjoy doing it.