I saw those challenges; I've only done 6 of them. All by chance as I played. Didn't go out of my way to complete any of them. Most are far from being completed let alone started.
You should test out your luck with the essences that change a normal gear to a rare. Find a normal wand or knife which has the base stat you are happy with; then give your luck a go and change it to a rare. Who knows; might turn out better than the one you currently have. Just remember to up the quality first before you change it to rare.
I played yesterday a bit; I got myself a new chest piece from the safehouse. Its a nice piece; I just need to try and get it to 6 link then re-arrange my skills again. I also got myself a spectre skill gem. Just leveling up the gem and giving the spectres a go. Currently they die easy; except when I use it on a bigger mob. It is pretty cool.
Ooooo I might try it on the giant lady statues next time. I wouldn't mind some Amazonian body guards.
Hummm; maybe I should give hardcore a go; just to see what it is like so I can prepare myself mentally lol
Also; did you know you can use commands in the chat to obtain some information? For example, click to hold onto a piece of gear; then hit enter and type /itemlevel It will tell you the item level of the piece of gear you are currently holding on your mouse. Also; /deaths or was it /death... either way; it tells you how times you have died lol. I gave it a go and I didn't realise I had died that many times.
There was another command which tells you how many skill points you have and which quests you are missing that give skill points as a reward. I think it was /passive