I don't think that all of these should get them but that they are good ideas: 
Gen 1: Arcanine, Dragonite, Muk, Machamp, Dodrio, Weezing, Ninetails, Electrode (maybe give it an ability that allows it to survive explosion on one hp and then faints the next time it uses it?), Tentacruel, Lapras, Snorlax. 
Gen 2: Starters, Furret, (Hey doesn't anyone think that sandstream on mega tyranitar is redundant??? I mean at least give it Mold breaker, Sand force or sand veil) Crobat, Xatu, Sudowoodo, Politoed, Shuckle, Weavile,  
Gen 3: Breloom, Mightyena, Linoone, Shiftry, I agree with shedinja, Wailord, Cacturn, Wiscash, Zangoose, Seviper, Deoxys (OP shit would be stance change like ability) 
Gen 4: Starters, Bibarel (but did you know 
, And also maybe with an ability that boosts HM moves), Drifblim, Chatot, Spiritomb, Toxicroak, ELECTIVIRE (One of my favourite f**king pokes) Porygon Z 
Gen 5: No starters, Leipard,  ExcaKILL, Krookodile, Scolipede, Zoroark (One of my favourite f**king pokes), Volcarona, Golurk, (too many legendaries) 
Gen 6: Mega da f**king starters, I haven't played X and Y so i wouldn't know. 
Finally if i had to take my pick i would choose: Arcanine, Crobat, Shedinja, ELECTIVIRE, Zoroark, Greninja.