The traditional 2-lever trigger your rifle came with can be made quite nice, with a nice crisp letoff. It can be taken down to about 1.5-2lb and remain safe. It is an excellent field-reliable design.
Is yours creepy or just heavy?
If it's got some creep, there needs to be some material removed. This is a really touchy process and best left to someone that already really knows what they're doing. If it's just too heavy, you can adjust it down to ~2.5-3.0lb simply by cooking off the epoxy on the trigger adjustment nuts and adjusting them. To go lower than that you'll need a new, lighter and LONGER spring.
IT IS CRUCIAL THE SPRING IS ALWAYS PRELOADED. THIS WILL KEEP POSITIVE FORWARD FORCE ON THE TRIGGER PREVENTING SLAM FIRES. IF THE TRIGGER IS NOT ALWAYS PRELOADED BY THE SPRING INTO THE FORWARDMOST POSITION, THE TRIGGER IS LIABLE TO "MISS" CATCHING THE SEAR AS YOU CLOSE THE BOLT. THIS IS NOT GOOD AND YOU'LL BE SENDING BULLETS DOWNRANGE BY SIMPLY CLOSING THE BOLT.
Otherwise, both Jewell and CG Xtreme offer drop in triggers for these rifles. Depending on the feel you're after and the use of the rifle you might consider one over the other.
I've had both in my SPR. The jewell can be set incredibly light, but I've never been able to achieve a crisp letoff with these triggers. They'll let off smooth but not crisp. Also, mine failed (wouldn't reliably release) the first time it was out in the rain. Actually, it was ok while it was raining, but once the sun came out and things started drying out, it quit working correctly.
The CG Xtreme is excellent if you like a crisp, safe, 2 stage trigger. Only bummer with it as far as I'm concerned is the lack of overtravel stop/adjustment...it has a LOT of overtravel.
If you go the CG route, you'll want the one piece "tactical" trigger shoe, and you'll want to be sure you let them know it's for an FN SPR, and needs the special #4 lever.