The current form of templates implemented within the core templates plugin are severly underpower and lackluster compared to community alternatives. Templater is a popular alternative to the builtin templates because it allows you to write scripts to handle how a template should be applied.
A large gripe of mine is the inability to have a frontmatter property within a daily note that links to the the next day and one for the the previous day. I can always use hotkeys to navigate between them but having the connections within the vaults links would be a nice thing to have when navigating via graph view.
Proposed solution
I believe that at a bare minimum level, the functions that are usable within bases filters could be exposed to users within templates. The data accessable through those functions is already available within the app and exposed to users, this addition would make the experience across core plugins more consistent. Users who use bases would already be familiar with these pre-existing functions and their behavior.
By sharing functionality between bases and templates, two plugins which already share similarities, they would mutually benefit from improvements to eachother. Further integration between these two plugins would be desirable. Bases: New With Template (for 'New' Button) asks for an integral link between creating new notes through bases without needing to specify every property within the base, cluttering up the view.
Basic scripting in templates via the functions from Functions - Obsidian Help. Allowing these functions to be used like [[{{date(now() + "1d").format("YYYY-MM-DD")}}]] to get a link to tomorrow for example.
In the meantime, try to use the community plugin QuickAdd.
For example, you can create a new note with a template of your choice, you only need to create a new template action within QuickAdd, click the flash icon and then, bind a key to your QuickAdd action through Obsidian’s default shortcut menu.
But it doesn’t end here, you can run macros and write your own JavaScripts to manipulate notes.
Finally, I agree the concepts of the core template plugin is “old” with underwhelming features for nowadays standards and could benefit from the latest developments in Obsidian!
The idea to re-use formulas from Bases is a great example how templates could be improved. Bases or not Bases, we’re talking about automation.