What are the different types of blends? So far I know: Aeromatic, Virginian (VA), and English
Aromatic (flavored tobacco), Virginias(sweet/grassy/hay), VaPers (Virginia/Perique), Perique(Fermented tobacco), English(Latakia is in it, the proportions are still being debated), Burley(nutty), Lakeland(A british styled aromatic using natural oils, rose oil, lavender, etc., acquired taste)
I know that aeromatics smell very nice, but the one I have doesnt taste at all, no flavor...
Is this a norm with aeromatics?
No, you just have to find the right blend. Also, if you can't blow smoke out threw your nose (without inhaling the smoke) you're losing a lot of flavor. Especially when it comes to these aromatics that lack taste but have great room note.)
Which types of blends have sweeter flavors? which have heartier / baccy flavors?
Sweeter... Anything with Virginias(naturally sweet) or Cavendish(made sweet with toasting and maybe some sugar water) Everything else has baccy flavors. Usually the darker stuff with have a more pungent smell and taste. Think latakia, orientals, burley. No added flavors just added tobacco. I'd recommend G.L.Pease blends or Hearth and Home blends.
Which types burner cooler? hotter?
If a tobacco is too dry, or contains too much sugar, cavendish or straight virginias, it has a tendancy to burn hot. You have some control over this and will master it in time.
Which types need lots of relights? which dont?
This question is too personal for an exact answer. It depends mostly on you. It depends on how good your packing is, how good your cadence is, how hard or soft you're puffing, the weather, the pipe, the humidity of the tobacco, whether you woke up on the left or right side of the bed today, etc. etc. It's got everything to do with how you smoke it.