I did the same 3 things you listed without the ultra lite kit. The thick trigger made a Huge difference for me. In addition, I put on a set of XS Big Dot sights to replace the puny/tiny OE sights, which helped me greatly. So, I would say they were the best things that happened to my Rami. I also got a set of Cool Hand grips in Blue from Amazon.
I've already ordered a set of LOK grips in their cross-check pattern for the RAMI which I should be receiving in a week or so. I have bought their grips before to put on my P-01 which I like, so I went back to LOK: made in USA + great feedbacks and reputation on multiple online site earned my attention.
The main spring replacement made some discernible difference in my P-01 although it did not smooth out that tiny bit of grittiness in the SA mode as the trigger is creeping past the wall to the break point (note: I am being very anal here because under normal or stressful shooting circumstances, a shooter will not remotely notice any of this trigger action snobbery!). I have been told to smooth out that tiny annoyance, I will have to change over the hammer and polish more internals, the sear, yada, yada... Not that crucial in my case!
I was holding out on changing the sights but I am afarid that these beady little OE ones are not going to work for me if I seriously should consider the RAMI as a main nightstand / CCW weapon, but then again my P-01 is already set up for that purpose. Oh heck, who am I fooling?! I know that I will be replacing them but can't do the sight replacement on my own (don't have the necessary tools / machine). I assume that this is the one which you went with?:
https://www.xssights.com/Detail.aspx?PROD=993210&CAT=8527Thank you for the thumbs up on the Thick aka "combat" trigger but CGW is currently sold out
Did you instal this trigger yourself?