Politically, it's probably smart to go with the advice of the most senior person offering advice, especially if they are in your direct reporting structure.
As another option, supposing that one person told you they prefer "A" and another told you they prefer "B", show the two options to a few of your good reps and let them break the tie. I demonstrate that I've done the right things for enablement by showing that our reps actually use them.
You have several products with release dates next to each other and limited resources, so what do you do? Here’s how you can think of this: first, identify the releases with the highest ‘tier’ or ‘priority’ (classification of release tiers vary company by company). The highest priority feature is typically the one with the highest impact in the market and that should get more enablement focus.
The first thing to do is figure out the "why" of the conflicting opinions. Perhpas it has to do with the incentives each stakeholder is responding to, or a resistance to behavior change of some kind. Either way, this can potentially help reconcile those differences and produce something that everyone feels equally invested in.
How is your sales team set up? Do you have a sales training counterpart? Or is the head of sales?
Ultimately, you’ll need to set up a mtg with that person + your head of marketing and you to review proposals and to ask them who’s input is crucial. You will never make everyone happy - you have to become the expert and make recommendations and make sure you are aligned with the head of mktg and sales vision.
This is challenging indeed and something I've had to deal with at every company I've worked for. What I've fund helps keep me and the business teams sain is to plan to launch features 14 days after the official planned released date. This makes product nervous most of the time, but most of the time they're also delayed so it all works out in the end.
I know that this is sometimes an incredible challenge. I think the challenge specifically is around balance.
A balance between: What are metrics indicative of your business / GTM goals? AND What you can control?
This requires leadership buy-in from multiple groups — ideally they would understand Marketing and Product Marketing (this is not always the case!)
Based on Your Goals, I would then identify metrics. Some examples below:
Goes back to the shared goals - which at a high level, are hard to argue with - revenue, cost savings, customer success, etc. Once you get that common agreement, then it's about the strategy / the "how" to get there. If there are disagreements here, I would start with trying to understand why and seeing it from both of their vantage points. Then trying to see if you can get them 1:1 to understand the other point of view or better yet, get them to talk to each other. Ultimately though if all that doesn't work, you may need to get a tie breaker that's someone else and who they will listen to.