Indeed, but the differential is that monitor lizards are typically far more active in zoos than iguanas. The model varies from zoo to zoo but typically you see monitor lizards in much bigger indoor enclosures than iguanas, which seem better suited to smaller exhibits.
Your idea also poses the question of whether Frontier reintroduce the concept of 'Mini-Exhibits' like they had in Zoo Tycoon 2013. Then comes the question, which animals are suitable for a mini-exhibit? Meerkats? Maybe, but also red pandas and pangolin, both of which are already established as habitat animals. In any case, the game does allow you to build indoor exhibits for the sake of realism, even if the system isn't necessarily designed with that purpose in mind, so I don't think it's necessary to create a new exhibit large enough to contain a crocodilian. Snakes are a different kettle of fish altogether - they can't be kept in open-air enclosures because they can swim, climb, and wriggle through tight spaces, so I'm all for the idea of slightly larger exhibits for big animals like the green anaconda.
We are on the same page on how the level activity should be a factor in determining enclosure sizes for animals. Just like the example I gave on the giant tortoises needing more space per size due to their lifestyle as grazers thus roaming a lot more than an ambush predator like the alligator snapping turtle; varanids in my opinion also require more space than other lizards of similar size that are less active. This is why having both varanids in the game (even the smaller Nile monitor) as habitat species is an exemplary decision by Frontier to subliminally inform people varanids need a lot more space even though minimum keeping conditions are still inadequate (imo) and comparable to that of less active lizards using the same 2.5 by 2.5 TL rule.(
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3) A silent revolution has indeed started, with the Komodo dragon, which hopefully will spread over to other varanids.(
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That being said, the values themselves set by Frontier for both the Komodo dragon and the Nile monitor are out of scale. 100 sqm for the Nile monitor and 240 sqm for the Komodo dragon would be more than sufficient - which were the values I had recommended on my accuracy feedback thread. This way you not only advocate for larger enclosures for these animals to promote improved welfare for active reptiles, but also stay within the boundaries of common sense so it is consistent in comparison to the minimum space requirements determined for endotherms in the game.
Another issue that needs to be kept in mind (other than active animals needing more space) is game design. Having less active animals constantly moving around in a habitat for animations sake would look silly, and the opposite, having active animals as glorified statues in exhibits would also look out of place. Even having constantly moving crocodiles already in the game does disturb me quite a bit, let alone having stereotypical "indoor exhibit" animals having those animations. These are the reasons behind the suggestions I've made in the earlier reply. Having an entirely new category like ZT 2013's "mini exhibits" wouldn't be feasible at this point as it will introduce a wide range of new fixed costs and we already have animals added as habitat animals in the game that would fall into that new category. Any new small endotherm should thus be added as a habitat animal from this point forward. All they need to do is lower space requirements a lot and make use of those animals as "space filler" species. The player can still build their habitats indoors if they desire. Even small arboreal animals can be added as habitat animals (requiring a ton of climbing space for vertical habitat builds) with the help of a future netting DLC for birds, sloths and small primates (including the lemurs we already have in the game - having them contained in 1 meter tall barriers doesn't make any sense even if the figure is increased to account for the jump height as they can gain traction off unclimbable surfaces that are too high to jump over and then use their hands to grab the edge; something a big cat or bear can't do with unclimbable surfaces due to weight and the lack of divergent digits to grab).
With endotherms out of question, we need game defined exhibits only for ectotherms. This is where my 3 exhibit model/size suggestion comes in. As we no longer have small mammals and birds to worry about, they'll all be glass exhibits typical of reptiles, amphibians and inverts (and possibly fish in the future) with three sizes: 2 by 2, 4 by 4 (the one in the game) and 8 by 8 to be used by the animals I described in the earlier post. Having exhibits ranging from 4 sqm to 64 sqm not only gives developers room to play with when choosing species, but also allows for a smoother transition to small habitat animal space requirements possibly starting from 50-80 sqm. Even having something like a pair of Cuvier's dwarf caimans that has a typical adult weight of 6-7 kg, which is comparable to the average weight of male green iguana at 4kg (9kg max), in a 64 sqm exhibit wouldn't only look neat but also within reason and international standards. Anything larger is out of question. A spectacled caiman for instance would be habitat.
I see this as the quickest, easiest and the only financially feasible method of including as many species as possible into the game meanwhile keeping it accurate and within the boundaries of common sense. Having a totally new "mini-exhibit" type of enclosure or having mesh/aviary/cage type exhibits using the same method the game has but with new materials, mechanics and animations would be much more costly. By adding just two more glass exhibits resized from the current one (which wouldn't take an hour to make), adding a few designs for the interior and then having a netting DLC for the endotherms simply with a new mesh or two (the term as used in game design - not to be confused with the word mesh I used earlier) to close up a habitat but using the same habitat mechanics is by far the cheapest but solid way of solving this dilemma without having to add new habitat categories, mechanics, systems, animation and rig types to the game that would cost hundreds of times more.