Compared to other ships of its size, the Imperial Courier isn't
cheap. The ship itself costs 2.5 million Cr, while an Adder which has a comparable (if worse) jump range costs 87,810 Credits. Of the small ships, the Courier is actually luxury-priced. Of course, both are quite cheap when compared to the "mainstream" exploration ships - a couple of untagged ELWs will pay for the price of the ship.
I'm flying a
Courier as an exploration vessel myself - alternating between that and a
Clipper. On my current Courier expedition, I've flown around 50 kly (and counting) so far, so it would have been enough for a round trip to Sag. A* and back; the ship's perfectly fine for that.
Without an SRV bay, my Courier does 41.87 ly on a full tank, while having a forward/boost speed of 504 / 684 m/s. See the build
here. You can go higher on the jump range (see my 44.86 ly build
here), but that's by sacrificing the other strengths of the ship. Personally, I like to know that I can easily survive an interdiction even without hitting the boost button.
Oh, and for exploration, you don't want bi-weave shields. Those are useful for prolonged combat, like in PvE builds, where you want to fight for a long time. Instead, you'll want as high shield strength as you can reasonably achieve, like in most PvP builds. You don't want to stay and fight (especially without weapons!), you want to survive the alpha strike and run away. If your shields drop, by the time a bi-weave would bring it back online, you'll either be dead or will have successfully run away.
Also, note my shield in the build above: an enhanced mod on a 2D shield will provide a bit better strength than a 2C bi-weave, while being much lighter.
As for fuel scooping and such: in my opinion, the Courier's default tank size of 8T is oversized. A 4T is fine for everything, especially with route plan filtering now, but even 6T is decent. On this featherweight ship, even that 2T counts for a lot. The fuel scoop size / fuel tank size ratio isn't very good, but with a 3A scoop and a 4T tank, I still don't need to brake for stars. Personally, I find that very useful.