Personally, I'm a big fan of Raichu lv X, it's got a great attack and it's Body that actually should be a Power is amazing. Problems with Raichu are low HP for one thing, it came out at the same time as Machamp so that was also problematic, the non lv X versions are kind of mediocre, the MT Raichu provides energy acceleration and can dish out strong attacks by discarding it's energy, the SF Raichu has a free attack for 30 which is decent, a second attack for 3 energy that is kind of situational, and a final attack that is powerful but discards energy. The main problem though is the bogus amount of Electric Energy needed to attack, lets say you lv up and use Voltage Shoot, first you need 3 Energy to do the attack, second you have to discard two energy from your hand so thats 5 energy cards needed, if you attack again you can either use burst ball which discards 3 putting your necessary Energy at 8 cards if you don't want to empty Raichu, if you Votage Shoot again you need 7 Energy, if you use Explosive Thunder you'll discard at least 3 but that will only get you 90 damage so youd need to discard 4 or 5 to get a good KO. As you can see Raichu uses way to much Energy and it can be a hassle to repeatedly get enough energy to dish out good attacks.