The first part of the title of this post is plainly obvious - your requirements for anything are going to be driven by what you need to get done and manage. But in the broader scheme of things, meeting your individual requirements may make your daily work easier, but will it provide the full breadth of benefits for your organization beyond making one person's or team's work more efficient?
Certainly garnering efficiencies anywhere is usually a good thing. But if you're going to invest in making a particular task easier, doesn't it make sense to examine other related savings opportunities that can be gained through perhaps a smaller (proportionally) incremental investment. For example if you're a DNS administrator, procuring a set of dedicated DNS servers, perhaps a DNS GUI for easier data entry, or even a DNS hosting service, may make life easier for you. But is this benefit of this "ease" provide the maximum return on the investment in one or more of these solutions?
One way to assess this is to consider how you interact with other members of your organization to accomplish your work. If you're managing internal DNS servers for all or a portion of your organization, you probably receive requests for new resource records for newly deployed devices and/or services or reverse domains for new subnets (e.g., new branch office or store openings).
Consider how these requests and your results are communicated and whether your proposed solution can streamline these communications. Many organizations communicate such requests through email or phone calls. Imagine a solution where other users can log requests, you review and adjust or approve them, you enact the change, then you communicate results to requestors without necessarily having to email back and forth. Such automation can save time and reduce mistakes otherwise possible with the transposition of information from an email to your DNS GUI. Your job will be easier and these other users will likely appreciate the faster and more accurate service you provide. And we could all do with a little less email!
Automating otherwise manual communication methods is one of the major benefits of investing in an IPAM solution. The larger the number of requestors and members of your team, the larger the potential error reduction and time and money savings that can generally be realized. Of course getting all of those affected by such a change in process need to be brought on board (by edict or consensus) but the benefits can be substantial.
Selecting a solution that provides an incremental growth path may be the way to go to start small with an extend-able solution (at least making your job easier!), make incremental deployments, and identify savings to feed subsequent broader deployments.