Yes!  You should definitely look at Marketo's analytics for this.  It an do both FT and MT attribution as well as a lot more.  Also, already integrated

I would do a lot of thinking about what you want to get out of this.

• Look for my article on Channel Offer Method
• Consider the FT/LT fields first
• Get a good process where you are actually tagging regularly.
• Consider all the reporting tools and what they need to show you want you want. RCE is good, but there are limitations, some of which can be handled with good data, others not.
• Brightfunnel or PathToScale are good options that get much closer to what most CMOs actually ask you, but there are still limitations with those as well.
• What else do you have working? In my Martech Maturity Model, I usually place Attribution visibilty at Stage 5, after Lifecycle/Funnel and Nurturing. So if you aren't even doing much funnel reporting now, do that first.