Cloud Based Alternatives to Suite CRM with Comparable Customization Capabilities

I know this is an awkward question to ask here but it’s a legitimate one. We are longing for a CRM with more updated interface. However we like to be able to make “deep” modifications and the hook system in Suite/Sugar serves that purpose well. Most cloud-based CRMs offer less customization capability (let’s call them “non-code level” customizations) such as adding custom fields or workflows. We need more control.

Is the latest Sugar really the next best alternative if we want to take it to “the next level” so to speak or does it still have a fairly antiquated interface (especially from the perspective of using it on desktops with large FullHD monitors)

Are there other solutions worth looking at that we can have “code-level” customization capabilities (or something very close)? We would still consider self-hosting, if that’s really the only option, but prefer to move to the cloud and let someone else manage the server and core code updates.

Oh come on, I’m sure someone on here who has done extensive customization of Suite over the years has done some recent evaluations of other solutions with a more up-to-date user interface (and better functioning built-in email features) ???