Who can I pair with Steelix?

I am currently working on a Steelix that I am close to obtaining.
Breeding has been painfully slow but I am coming to a near end with 30-31 IV on attack, defense, and either sp.def or speed. Unsure about EV spread.
Would going that route (and unsure of the nature) be alright or best for a tank trapper? Unless another type is more preferred?
My steelix will have Rock slide and Block. I am still unsure about the last 2 moves.

Possible combinations I am considering are the Rock slide and block mixed with the following:

• Sandstorm and protect
• Double-edge and Dragon breath (rock head)
• Iron Tail and Dig
• Sandstorm and Dragon breath

If I don't put a lot of attention on Sp. Def. would the ability sturdy still be helpful?
Due to speed, expecting to cause flinching is low... If I use him as a trapper, maybe I can have him do sandstorm together with a dugtrio/sandslash that has sandveil and toxic? Ideas? :-)

what are you breeding this steelix for? like, what battles?

if it's just for ingame, just run eq/irontail/rockslide/doubleedge with rock head and adamant nature since its base 85 atk is kinda poor even by adv standards.

if it's for a challenge like battle tower or something, it's pretty outclassed by other pokes, but if you only have access to frlg pokes it can do ok. i'd just make it a tank with choice band and explosion instead of double-edge (so you can run sturdy to prevent horn drill etc spam). you can also toss in toxic if you want.

either case, block is really pointless since the ai almost never switches. sandstorm is very inefficient and doesn't deal damage like a move like toxic would. dragonbreath has terrible damage output so i'd avoid it.

Ideally, I only plan to use him for double battles with friends. I don't have access to any choice bands. As far as battle tower goes, I don't utilize it enough to bother. I thought about toxic a little more, but I don't like the idea of having him do that because I would prefer to have toxic stay in battle (also consider his slow speed) rather than see the opponent switch out by doing it in one turn so I would want to leave that to cacturne who can also benefit from a sandstorm and even throw spikes afterwards. For my purpose, would that do just fine? I decided to pull sandslash out because of surf. Plus he can heal against water types with giga drain!!