Also I wanted to know more about SIGE's alternatives but finally all my investigations on this question had shown SIGE as a best solution for me.
The setup of SIGE was easy for me as a Joomla's newbie. I'd understood its work principles very fast. During configuration and applying SIGE with my images I found it as a very easy-to-use gallery with possibility of setup main features thru Joomla's backend and using a couple of overriding keys for each case in my articles. All I need is just prepare set of my photos, put them to a folder and write the gallery code to the material. I don't need think about generating thumbnails - SIGE does it itself well. Showing pictures in different modes (for ex. Light Box) is great.
I've encountered some problems with reading CP1251 Cyrillic characters from IPTC tag. I just had tags encoded only that way 'cause writing IPTC on Wintel in UTF8 is not so easy. Support was very fast and good - problem had been solved quickly.
SIGE is used on a travel agency site for the moment. And I suppose I will use it in my further projects too.
Many thanks to SIGE's developer!
Thank you very much for your review!