I really think you should try for Tynamo. Just looked at its shiny sprites on Bulbapedia and it just look awesome. But you know what ? I just noticed that Tynamo is foundable at 5% at the Seaside Cave, where no other Electric types are, if you were afraid of Joltik! Of course, there's a Woobat there, but there's also Boldore, Golduck and Seel, wich are very interesting Pokémon too! If you go on the other floor, 5% of chances of encountering a Eelektrik and Seel is replaced by Shuckle. You should go take a look here
Good luck !