It's very common to look for solutions to playing deficiencies by purchasing stuff. I encourage people to resist the urge to find playing solutions through equipment changes whenever possible. Regular practice and performance are the best ways to solve playing or tone deficiencies.
Having said that there are times when adjusting your equipment will help you perform or practice better and in those times spending $ is a good thing.
No one here can evaluate whether changing strings is an assist to your playing or an attempt to shortcut practice by buying stuff. Talk with your teacher and try to figure that out with them.
I did some time playing steels/spiros/whatever on a rental bass and I didn't at all feel comfortable. I worked on right hand and left hand technique, but still this feeling was there. I got my own bass, started out with jazzers which just felt wrong to me, then I got Obli's which felt OK. It was a true revelation getting my Velvet Garbos after four years of struggling with steels/high tension synthetics. The Garbos really let me to "come out" in a sense. I felt at home, and now when I play guts, that feeling is enhanced. What Uncletoad said is really true, in my case the change of strings really made an important difference in my musicianship and has helped me to fully express myself.


