AK47 is only "bad" if you don't like it's specific traits. it doesn't sound interesting to me because everything i've read says it can get stinky & stoney.
you can get too much of a good thing with big too, especially indoors, but generally, the bigger & slower growing strains have the best buzzes.
i haven't tried TGA subcool's gear yet, but it's much loved and a recent remark i heard about said his sativas aren't watered down and another person that only likes getting stoned didn't like the ones he tried because they got him high. that sounds great to me. i can't wait to test his jack's cleaner 2, but his jack the ripper gets many raves and is pretty fast finishing for a sativa.
you might be interested in sannies' killing fields too. there's a good sized thread on that one here and someone said it's "talk to your dog trippy" in another thread.
out of what i've tried so far, these are my 3 favorite strains... all sativa dominants...
haze x skunk - high quality seeds... nice and affordable, super potent, long lasting buzz you can still feel a bit the next day, tolerance doesn't seem to build up much, nice euphoria levels, nice motivation (it got me off beer and on to an unplanned diet by ignoring hunger & staying focused on whatever i was having more fun doing. it has a SLIGHT bit of lead eye in it's buzz, but the motivation is stronger and it doesn't get in the way of staying busy. it's not as trippy as columbian gold, but it's not shabby either.
8 miles high - mandala... i loved it! it was the first genuine high i'd had in years, though C99 is racier, but also more clear headed. it has a nice energy neutral buzz with no couchlock, but isn't racy either. it just leaves you with a happy mellow glow that's eager to have fun right away. instead of trying to build the buzz on that, i took just a couple hits and put some tunes on & started dancing. a lot of sativas, kali mist in particular, are too clearheaded and racy to be able to chill on tunes with, but 8MH likes anything fun. it's a perfect goldilocks buzz that does everything just right. haze skunk will eff you up if you overdo it like a lot of trippy sativas do.
super cali haze - short stuff... it has a very similar buzz to 8MH. it's less into music and maybe less trippy, or at least physical, but it has great euphoria and motivation going on, but what REALLY makes it special is the DELICIOUS sweet grapes taste that's more authentic than overrated blueberry with a much better buzz too. it's very exotic and smoked so much like the tiny 1/2 gram of "real" (or was it the same thing?) haze i was gifted, i couldn't tell them apart with a side by side comparison.
kali mist - serious seeds... is THE strain you want if you don't plan on sitting still at all. it's off the charts energetic and pretty clearheaded, but also has super high levels of euphoria. i planned on tripping out to tunes on it, but couldn't and instead cleaned house grinning from ear to ear. i would NEVER pick it as the only strain to grow because it's buzz is for activities only, but i loved it so much when i smoked the original crushed red pepper pheno (now just spicy & fruity), that i begged to buy an eighth and quit bidding at $120. i'll take any of the three strains above it first though as they're all trippier, and easier to relax on, but without making you tired. before i grew KM too, i'd go with C99 which finishes in just 45-50 days where KM takes a full 17 weeks where you find pure sativas.
if you want something else that's exotic & like the taste of black licorice, you might get into durban poison. it has a nice sativa buzz, but wasn't as trippy as columbian gold despite it's rep & comparisons to thai, and i don't like licorice & it gave me dry heaves, but it was totally worth it as it was the first real high i'd had in 10 years when i blazed some around 1997.
if you're looking for top quality, everything i've read says that TGA's gear and sannies' killing fields are going to give it to you until you start looking into 15 weeks plus pure landrace strains that are going to get tree sized. look into ace seeds or panama red & black haze for undiltued slow growing giant strains.
a short strain with a short flowering period will give you more harvest. that's why indicas dominate the street scene, but the bigger & slower strains will give you the trippiest buzzes.
BTW, sativa seeds' full moon (highland thai) is DELICIOUS if you get a tutti fruity pheno, but it's going to be slow & fussy like the other landrace strains at the bottom of the list, and just like in the wild, it can turn hermie on you, but that's a sign you're not getting watered down genes. it was too much trouble for me to grow, but is one of the top strains i wish i could try mature bud for. it's trippy too.
hope that helps