I would approach the subject of the choice of a first Panerai in a different manner.
I note that all the models that you have refered to are Luminor models. One can deduct from this fact that you are not interested in buying a Radomir model.
This having been said my main question to you is do you want a mechanical watch or an automatic one? Note that mechanical watches do not come wth the date and you have to wind them up regularly, whereas automatic ones (usually) come with the date and if you keep them on your wrist they don't need to be wound up as regularly.
This basically gives you three categories to choose from:
1. Luminor base: mechanical, hour and minutes
2. Luminor Marina: mechanical, hour, minutes and seconds
3. Luminor Marina Automatic: automatic (as one could guess), hour, minutes, seconds and date.
I think that it is great to start with a somewhat standard model as it gives you the opportunity to go more up scale in the future (besides the fact that they are all simply beautiful). Basically it gives something to look forward too.
I like your choice of the PAM 177 simple yet elegant model. Titanium is a very elegant choice from my perspective.
If you don't care about moving up in the future then the PAM 212 is the one I would go for.
Good luck with finding a PAM 36.
George