I'm trying to figure out which way to go here and I am struggling to narrow it down. I have five original S1's. I have not heard Nrt or S2's. I know many of you started with S1's before moving up the chain so looking for some imput from those of you to get a feeling of which way to lean on the upgrade path. Money is unfortunately always an issue

Option 1: get S2 upgrade kits for LCR at about 1200. and add another sub, 6 to 800, to go along with HSU sub.

Option 2: get standard sierra towers, no extra sub and maybe push the budget up and add Horizon center. ( that reaches the $ cutoff point ).
I am looking to gain better mid bass and add some more punch there, which maybe the towers would provide better that S2 and another sub ??? Yes...No.....

These are earlier S1's, and from the measurements I don't think I'd have to mess with enlarging the woofer holes for the S2 woofer but these are B stocks, L&R look good ( all are natural finish ) but current center has a broken corner which is hidden by being shelved under TV.
Current room is about 14 x16 with sloping ceiling. Sounds good now but other concerns are in a year or so may be moving into larger listening room.

So if you were in this similar spot at some point....which way did you go.......S1 to S2 or S1 to S1 towers?
Hoping to make this the final speaker upgrade.