Once you start asking for advice, you will be overwhelmed with opinions :smile:
You could certainly turn the process of keeping your MINI clean into a full time job - sort of putting the "detail" into "detailing".
For glass and clear stuff I use Stoner Invisible Glass. It's about $3 a can and gives a great, streak-free shine.
For chrome you can use Eagle One "Nevr Dull" which goes for about $5 a can. It cleans well and leaves a nice lustrous shine. I find it to be quite good.
For the plastic and glass, there's a whole host of possibilities from Armor All (which now comes in several "flavors" of shininess) to Zaino Plastic Cleaner and other specialty formulations (Mother's Back to Black and others). I've tried several but not yet settled on any one. The Zaino stuff is pretty good.
And of course, the waxing could (should?) be preceded by clay bar and then application of swirl remover before waxing. And then there is "the great wax controversy"....

[do you use Zaino, Zymol, 3M, Meguiars, Mother's...carnuba or polymer-based...how many coats...do you need a sealant...]...and don't even start to ask about what kind of towels to use...[cotton, microfiber, watch out for those nylon threads!, tear off the tags! consider cutting the edges off!]
Oh! And the wheels! Don't forget the wheel and tires! Take the wheels off, wash them with mild soap then polish them with Wheel Wax (about $15 a jar) and then put them back on. If you like that shiny tire look then use some tire treatment.
It's a slippery slope!