BL is not just for looks... with a BL you can fit up to 33" tires with little to no trimming... even if you do a SL it won't increase the size tire you can run...


Tanker you can also do what is referred to as a poor man's lift (PML) it will give you 1.5" of lift front and rear for the cost of shackles and shipping. you can the set from www.4x4parts.com for $65+shipping. Here is a link to the shackles: https://www.4x4parts.com/nissan/xterra-rear-lift-shackles-p-145.html
Also the How to threads from www.clubxterra.org
Index torsion bars (this is how you lift the front)
http://www.clubxterra.org/forums/showthread.php?t=2600
Reindex torsion bars (this is what you do if you run out of threads on the adjuster before the desired lift is acquired)
http://www.clubxterra.org/forums/showthread.php?t=2554
rear shackles
http://www.clubxterra.org/forums/showpost.php?p=194769&postcount=3
Also this thread from CX is very informative about all types of lifts.
http://www.clubxterra.org/forums/showthread.php?t=28090

Also something to look into adding to complete you PML which would be the most expensive part would be to add shocks like ranchos or billstiens that are meant for a 3" lift. With the added flex you get the stock shocks will act like limiting straps when the axles droop. (you can even run the 3" lift shocks on a stock setup incase you do eventually lift the truck)

Ranch Front $45/shock (you'll need 2)
https://www.4x4parts.com/nissan/rancho-rs5000-front-shock-p-1855.html
Ranch Rear $45/shock (you'll need 2)
https://www.4x4parts.com/nissan/rancho-rs5000-rear-shock-p-1856.html

Bilstein Front $61/shock (you'll need 2)
https://www.4x4parts.com/nissan/bilstein-front-shock-p-1924.html
Bilstein Rear $61/shock (you'll need 2)
https://www.4x4parts.com/nissan/bilstein-rear-shock-p-1925.html

So a brief roll up:
BL = about $75

PML = about $65+shipping

PML+shocks:
Rancho = about $245+shipping
Bilstein = about $309+shipping