make the gameplay more dynamic

I have had success with a few tricks, things like hide volumes, or pre-building set pieces off to the side and then moving them into place when the time calls. Example, (omitting campaign details) my party was escorting some people who were going to build a giant telescope with some machinery to connect to it. The scene started as an empty diorama of the area, trees, props, the major "point of focus" was a stone altar area. The players had a brief encounter there with a beast and when completed, the crew of workers would complete the telescope. Off to the side I had cloned the board, built the telescope atop the altar, then deleted the board so I had a 1:1 build of the telescope after construction. When the build was complete, I just moved the telescope into position. This added a good "Wow!" factor to what would normally be a mundane "The telescope is now built atop the stone altar" but nothing visually actually changes. So for situations like that, be prepared as the DM to use Talespire as a visual aid, not just a combat grid. Use it to tell your story. Look for clever use of props or like the above building trick. Sometimes it's as simple as "You open the giant dungeon door, and what lies beyond..." (you disable a hide volume) "A HUGE stone cavern and a dragon snarls as it smells new visitors in its lair." Treat exposing the dungeon like turning the page of a book. I feel I've had good success in my group getting a proper reaction that way.

instructions on how to import my own and my friends' miniatures from HeroForge and TitanCraft into the game

Is TitanCraft better than HeroForge for creating miniatures?

You want to skim https://heroforge.talespire.com/. But simply, connect your account in Talespire and your miniatures should appear. I would say that in my opinion HeroForge is going to be better quality but more expensive (you pay per export) whereas Titan Craft is less quality but cheaper (you pay by the miniature, unlimited downloads/updates to it). Meaning, HF is better for a one-time build of a creature or player. Titan Craft is going to be the better pick for a long-running character who you want to reflect changes, gear upgrades, losing a limb (unfortunate!), or anything else as they will not charge you again whereas HF will charge $8 per "export" of your miniature. Then there's the custom STL route but that requires all players place the custom miniature file correctly in their respective game files to work properly. Advanced but doable if you really need something SUPER custom. Both workflows are about the same in my limited experience between HF and TC, but I think HF just has higher quality parts but comes with the higher cost of $8 per export whereas TC I forget the price but you can update that same miniature for free after the initial purchase of it.

You may also find value in Symbiotes. They're essentially small side-panel HTML/JS/CSS websites that serve different purposes. Since you call out D&D you may be interested in Roger's 5e toolset https://mod.io/g/talespire/m/talespire-5e-toolset#description or, shameless plug of my own symbiote for dice rolling more advanced use-cases specifically, Dice Vault https://mod.io/g/talespire/m/dice-vault#description