Just because something is unpopular, it doesn't mean it's neccessarily better...
Choose what appeals more to you- I'm never putting the colored or not screen into consideration myself, I like black and white tamas and color ones equally. Just TF is more of an actual pet than anything else, while iD L is both a pet AND life simulator. Here's what both versions have, in a nutshell:
Tamagotchi Friends:
Greyscale screen (not like the older tamas)
Four or five games in total, two available at first
Characters mostly derived from P's, but some from iD L are in there as well
Jewerly shop (the jewerly doesn't really do anything so far, you only collect it)
Food shop
NFC communication
iD L:
Colored screen
Being able to change wallpaper in every room and to download additional living room wallpapers (you can even make yours)
Fridge, restaurant, bakery and eating at parent's place functions, also being able to grow your own food like fruits and vegetables via seeds. Also downloadable.
Your pet can have a pet too
Two built in games, you can download more via irda
Many unlockable locations that you have to work for
You can let your character wear clothes and accessories (and download additional via irda as well)
Irda communication
Items your character can play with, also seeds that you can plant to get items or food (you can download additional ones as well, both seeds and items), also cleaning tools
Certain characters can change appearances into their alter-ego forms (Henshin Jo)
And there is probably some more.
I really don't know where you've read that iD L has less features... In fact, Tamagotchi Friends has less features than previous releases (US connection era- color tamagotchis have nothing to do with US releases) and has very poor manufacturing. Many people don't enjoy it, but it's just their opinion- maybe you would like one? But it depends for what features you are gonig for. Also, consider buying a japanese iD L if possible- seriously, language is not a barrier, and it will be way cheaper. And P's is even better, in my opinion, even if it doesn't have an english version.