It doesn't help that the guides on Steam covering power are misleading to the point that a new player would be confused and might think block reactors are the way to go.
I know this was awhile ago, but did you ever post it or do you still have the design?
I PM'ed you my reactor design so you can take a look at it but please bear in mind that these block reactors are very inefficient. The reason, is because they have a lot of groupings and the more groups of reactors you have the worse your ship's power efficiency becomes. Sure, your ship will make more total power with more groups, but each individual module on your ship will go down in efficiency.
Each reactor module you place (no matter how you place it) will always generate a base 25 e/sec. Efficient placement, IE: lines and such, will award you bonus power. This bonus power
hard caps at 2,000,000 e/sec, total ship power generation does not hard cap, only the bonus does, which is why people choose to call it a soft cap. Getting all of the 2 mil e/sec bonus is actually somewhat difficult to achieve, unless your ship is extremely large (a single group of reactors 5,164 meters long, is the minimum needed to get all of the 2 mil bonus power.) If you do manage to reach this cap, every reactor placed after that will only give you 25 e/sec.
Back to the reason why block reactors are inefficient. It is always preferable to add to a group of reactors than it is to create another group of reactors (as far as efficiency goes.) The moment you start a new group, that is the moment ALL reactor modules on your ship go down in efficiency. This isn't that big of a deal usually, nearly all ships have multiple groupings, but this is especially important when building a cloaking ship where efficiency is your top priority. For reference my
stealth ship only has 4 reactor groups, a necessity since i didn't want her to be excessively long. With 5 groups I could have reduced the length even more but each reactor module would not be able to cloak as much mass as the 4 group design. You will notice that many cloak capable ships on the dock use a ton of reactor groups to produce a great deal of power, and while this works, they are imho missing the mark. The ship is capable of cloaking, jamming and all that but it is, more or less, a blob of flying reactors with little detail. If they would consider individual reactor efficiency, when designing their cloaker, they could enjoy a bit more creative freedom.