It should not be restricted at all...the only reason my Warlock is doing well is that I understand positioning during a fight. Warlocks are a class that gets 2 spells per fight, then up to 4 at the highest levels. Right now I have had one short rest through 2 levels...cantrips and daggers only.
When it comes to the rules in 5e Larian...whatever you do...Do NOT think!...just implement. Every deviation you make will bite you in the bum. Look at SSI of the 80s and 90s as your turn based model for success. Just implement the RAW and put your creativity elsewhere.
Apples to oranges.
SSI was dealing with AD&D, a system designed from a minis wargame that expected you to have mini's (all ranges are given in table "s) & dramatically changed ranges between the dungeon & overland travel.
5e was designed to be run on a table as an option, but mostly to 'feel' like D&D and be easily run in the head of a DM. The motto for the design of this edition was "Rulings, not Rules" which is the exact opposite design goal of AD&D and also a nightmare when attempting to have a computer execute the rules set.
If you implement 5e on a computer, by virtue of how the game was designed, you
have to make changes, choices and Always rulings and in general they've done a fairly straightforward port (aside from range) and...well...5e's rules just aren't that interesting and strategy isn't that deep when it comes to combat. Intentionally so. The DM, through rulings, was supposed to patch over any bumps.
Back on topic - Limiting Short Rests & the so far nearly unlimited Long Rests essentially means we're back to 3.x 15 minute workday where the Cleric/Wizard/Druid are king and once they're out of spells, why bother going further? Might as well Rest.
Especially with the high-difficulty of each combat.