KidA said
Is having your 12th house lord in the 1st house similar to having Neptune in the 1st? Think about it, just wanted some feedback.

Hmm... On one hand I'd be tempted to say the following: it can be similar to that, to have a Pisces-ruled 1st House, but with the ruler of the 12th in the 1st, the similarities with having Neptune in there can only be very, very vague, unless there are other more consistent exchanges of energy to solidify a Neptune/1st House pattern. 
On the other hand, I have my 12th House ruler in my 4th and my childhood household totally lacked boundaries and definition, but then again I also have my Moon squared by Neptune to confirm that. This is a more consistent exchange of energy however and I think it's the main indicator. I don't think this energy would have played out so strongly if it was just my 12th House ruler in 4th. I think a placement like the one you mentioned can "confirm" a pattern. 

The house with Pisces on the cusp has Neptune (modern) as it's Lord and whatever house Neptune is in, that is where Neptune is. The Neptune energy is in the Pisces house/s. Planets, points and houses in Pisces have the Neptunian energy. Traditional Astrology had Jupiter as ruler of Pisces. The planet Lord of 12 that is in the first would be what it is by planet, with it's own meaning and sign, and that sign 's ruling planet  would have it's energy in the first. Think about that.