I must admit something. BG series is, for me, the best game ever. I haven't stopped playing for years now and I practicaly live in Amn. Currently I'm playing 2 paralel campaigns - a solo and a full party. I don't even remember how many times I started a new game, but it's at least 70-80 times. With tons of mods and it's replaying value it never gets boring.
It's hard to compare BG1 and BG2. You must play both and decide for you.
Talking about the BGtutu mod (and it's called that because it makes BG one transfer to BG two settings), it now works with few bugs and is great for one who wants to play the whole saga from the start. The only problem is that it could make BG1 a little bit too easy if using BG2 class kits and features like dual-wielding and some other abilities.
When installing mods for BG2 me sure to use the right order to avois screwing your game:
BG2
TOB expansion
TOB patch
Baldurdash fixpack
non-weidu mods
weidu mods - they can be installed in whatever order you like
I suggest using weidu mods and avoiding non-weidu.
If you want to play BG1 with BGtutu mod you must install both BG1&2 and follow the instructions.
I wish you happy adventuring.
k: