What you want is totally normal and to be honest with you, if you two have been in a relationship for 7 years and you've known he was more of a sub/has a lower sex drive then you, these are things you may not be able to change about him.
When I've dated less sexual partners and ones that are more subs then dom's they don't really fair well trying to be anything but what they are. Some can get into dom if they try, but it can be hard espically if they are like your guy "innocent and don't want to hurt you". At least that's been my issue with guys.
The only thing you can do is one of two things. You can talk with your guy about this and be frank, but in a kind way about what it is you desire. Say that it is something you both need to be happy (don't make it all about yourself or rather don't say "I want xxx" and "I need xxx" from you; just be careful about demands) and see if there is anything he desires that you can do in return?
If this is something that you two have discussed or things have been the same for whatever reason then you have to start to think to yourself is this what you want? I know that it's not easy to think about this since 7 years is no joke, but you have to think to yourself if you are truly happy with how your sex life is atm because if that is something you cannot sacrifice then this is something you have to consider and talk about.
I know I am the same as you, I like to be a sub and I need a dom partner. I don't mind them wanting to be more submissive, but sex is an important part of a relationship to me, just as much as the emotional side so I can't be with someone who can't at the very least try to pleasure me or enjoy sex. Toys are a great alternative to getting off especially if you are hyper-sexual (it's a curse I tell you lol), but you have to be happy because if not you can grow to resent it. I knew that when I started to fantasize about other men (not just my 2D waifu's but I was seriously thinking about being with other men, that the relationship was doomed for me and it was a long term relationship). That wasn't the only reason I got out of it, but it was a partial element.
I wish you two the best and furthermore for your happiness. I hope this issue can be resolved, it's not easy so best of luck (^^)
on a side note I'm still so sorry for that one response I gave you, I felt so bad when I re-read what I wrote, never meant to come off so bitch. Fully regret not thinking before posting, gomen (TmT)