Congratulations on your acquisition. Along about 2004, Hanwei reduced the blade width on the practical (and several other models). The XL models went with a return to the beefier swords.
All bamboo is not created equal but green is definitely a better target than dried. A somewhat common error is using the middle of the blade as a striking point. Edge alignment is important. Some blades get bent even on 2 litre water bottles. Try not to baseball bat when slicing. Apply the brakes on the other side of the target and use the front third of the blade. It is the cuts and blows that don't cut cleanly that are most likely to stress a blade. I had tried cutting some very tough and thick cardboard tubes with my practical a few times but discontinued doing so.
Wet newspaper rolls, beach mats (watch out for wire edging) tatami, pool noodles soft rubber hose. I would avoid dried hardwoods. We have used pvc filled with dowel for stand pegs and it is not uncommon to cut both pvc and dowel (and chunks of stands). Dowels and bamboo iun the center of tatami, not an unusual target but the same maxim of cutting through is important.
When holding with two hands, you are applying pressure towards your wrists, kind of gently wringing the handle. A friend spends time first thing every morning doing 100 air strikes with his bokken (wooden sword).
Some complain about the Hanwei tsuka (handle) shape as being too straight but as a first sword (really any sword) one learns any tool in time. If using the sword mostly for decoration, you will probably want to learn different sageo knots
http://www.ksky.ne.jp/~sumie99/sageotying.html
http://www.way-of-the-samurai.com/how-to-tie-a-sageo.html
https://sbg-sword-forum.forums.net/thread/31529/sageo-presentation-knot
If displaying the katana out of the saya, be very aware of the hazard as well as keeping in mind that oil attracts dust, dust attracts moisture. Any sharp can be a hazard, even handling in their scabbards and saya. Sharps are always loaded. When handling indoors, note overhead and the space around you.
Enjoy!
GC